Open Access
How to translate text using browser tools
15 November 2022 Revision of some Malagasy forage grasses and their relatives within Brachiaria, Echinochloa, Moorochloa, and Urochloa
Maria S. Vorontsova
Author Affiliations +
Abstract

Vorontsova, M.S. (2022). Revision of some Malagasy forage grasses and their relatives within Brachiaria, Echinochloa, Moorochloa, and Urochloa. Candollea 77: 199–236. In English, English and French abstracts.

This work presents a revision of 31 species of Malagasy panicoid grasses (Poaceae subfam. Panicoideae, tribe Paniceae) traditionally placed in the genera Brachiaria (Trin.) Griseb. and Urochloa P. Beauv., including nine species endemic to the island of Madagascar, and 14 endemic to Madagascar and the surrounding islands. Phylogenetic research is ongoing and only a partial rearrangement of generic concepts is presented. Six new combinations are published, placing Malagasy and regional endemics previously known as Brachiaria in the genera Echinochloa P. Beauv. and Urochloa respectively: Echinochloa hubbardii (A. Camus) Voronts., E. leandriana (Bosser) Voronts., E. serpens (Kunth) Voronts., Urochloa humbertiana (A. Camus) Voronts., U. nana (Stapf) Voronts., and U. pseudodichotoma (Bosser) Voronts. Moorochloa eruciformis (Sm.) Veldkamp is accepted. Four names are placed in synonymy for the first time, 18 lectotypes are designated for names used in Madagascar, and known occurrences are mapped.

Received on May 9, 2022. Accepted on October 4, 2022. First published online on November 15, 2022.

Vorontsova, M.S. (2022). Révision de certaines graminées fourragères et apparentées à Madagascar dans les genres Brachiaria, Echinochloa, Moorochloa et Urochloa. Candollea 77: 199–236. En anglais, résumés anglais et français.

Ce travail présente une révision de 31 espèces de graminées panicoïdes malgaches (Poaceae subfamily Panicoideae, tribe Paniceae) traditionnellement placées dans les genres Brachiaria (Trin.) Griseb. et Urochloa P. Beauv. dont neuf espèces endémiques de l'île de Madagascar, et 14 endémiques de Madagascar et des îles environnantes. La recherche phylogénétique est en cours et seul un réarrangement partiel des concepts génériques est présenté. Six nouvelles combinaisons sont publiées, plaçant les endémiques malgaches et régionaux précédemment connus sous le genre Brachiaria dans les genres Echinochloa P. Beauv. et Urochloa respectivement: Echinochloa hubbardii (A. Camus) Voronts., E. leandriana (Bosser) Voronts., E. serpens (Kunth) Voronts., Urochloa humbertiana (A. Camus) Voronts., U. nana (Stapf) Voronts. et U. pseudodichotoma (Bosser) Voronts. L'espèce Moorochloa eruciformis (Sm.) Veldkamp est acceptée. Quatre noms sont placés en synonymie pour la première fois, 18 lectotypes sont désignés ici pour les noms utilisés à Madagascar, et les occurrences connues sont cartographiées.

Introduction

The Poaceae are recognised as probably the best documented large family of angiosperms and a model group (Hodkinson, 2018), responsible for the majority of human calorie intake as rice (Oryza sativa L.), wheat (Triticum aestivum L.), and sugar cane (Saccharum officinarum L.), as well as being architects of grasslands and savannas across the world (Kellogg, 2015). The ongoing taxonomic and phylogenetic research on the Poaceae diversity and evolutionary history has been compiled into the updated phylogenetic family classification, with the majority of Madagascar's Poaceae placed in the subfam. Panicoideae (Kellogg, 2015; Soreng et al., 2017). Of the tropical lineages in the Panicoideae, tribe Paniceae with c. 1,227 species (fide Soreng et al., 2017) comprises the commercially significant tropical forage grasses previously placed in the genus Brachiaria (Trin.) Griseb., now referrable to the monophyletic Urochloa P. Beauv. s.l. (Kellogg, 2015) in the subtribe Melinidinae. The full evolutionary history however remains unclear, with a significant number of superficially similar panicoid grasses not yet assigned to tribes with any degree of confidence (Zuloaga et al., 2018).

The Urochloa (Brachiaria) forages are significant for tropical pastures worldwide, and for pastoral livelihoods in sub-Saharan Africa (Bogdan, 1977). Much of the taxonomic research effort into Urochloa s.l. has been focused on Asia and the Americas (Morrone & Zuloaga, 1992, 1993; Veldkamp, 1996; Torres Gonzales & Morton, 2005), with tropical African and Indian Ocean taxa being treated more briefly in the context of flora projects (Fish et al., 2015; Sosef, 2016; Bosser & Renvoize, 2018). The basic biodiversity documentation of these forages and related taxa remains incomplete especially in Madagascar, where the phylogenetic placement of endemic species has not been fully established (Hackel et al., 2018) and a full Poaceae inventory has not been attempted (Vorontsova et al., 2016). Malagasy grasses with panicoid spikelets arranged in panicles were described by Camus as Panicum L. for largely open panicles (Vorontsova, 2018), Brachiaria (Camus, 1925, 1935, 1947, 1950, 1954, 1957) for compact racemes with lower glumes towards the rhachis, and Urochloa for compact racemes with lower glumes away the rhachis (Clayton & Renvoize, 1982). It has largely been assumed that all species of Brachiaria fall within the expanded and monophyletic Urochloa s.l., but the situation in Madagascar is more complex with a significant number of panicoid grasses falling within the Boivinellinae and therefore not belonging to either Panicum s.str. or Urochloa s.l. (Hackel et al., 2018).

This treatment follows Vorontsova (2018) for Panicum s.l. and aims to establish species concepts for all Malagasy grasses traditionally placed in the genera Brachiaria and Urochloa. For six clear members of the Urochloa and Echinochloa clades where morphology is in agreement with DNA sequence data, new combinations are made to place species in the correct genera. Species belonging to parts of the Boivinellinae and the Melinidinae where evolutionary history is not yet clear are retained in the genus “Brachiaria” pending future arrangement of the generic concepts (Appendix). There is currently no reliable set of characters that can consistently separate members of the Urochloa clade from the other taxa, although most species of Urochloa have racemes with a winged rhachis. Echinochloa P. Beauv. is easily distinguished by its lack of ligule. The genus Moorochloa Veldk., represented here by a single species in Madagascar, is an independent origin of Brachiaria-like grasses in the Melinidinae with spikelets disarticulating above the glumes, inconspicuous callus, and a chartaceous to cartilaginous, shiny, smooth and muticous upper lemma (Veldkamp, 2004).

Materials and methods

This study focuses on Madagascar and only the species occurring on Madagascar are included. Synonymy is restricted to names applied to collections made in Madagascar. Species descriptions were compiled from specimens collected in Madagascar and the Mascarenes and held at P: please note that the descriptions aim to represent these species both in Madagascar and the Mascarenes; morphological variability occurring outside these areas may not be represented here. For a full account of Poaceae of the Mascarene islands see Bosser & Renvoize (2018).

The distinction between grasses native to Madagascar, naturalised, or even recently planted introductions are not always easy to infer. Since during practical work in Madagascar there is no choice but deal with introduced taxa alongside native, this treatment records all species occurrences including those known to be introduced. Five of the species treated here have been listed by Bogdan (1977) in the top 45 tropical forage grasses: Urochloa arrecta (Hack. ex T. Durand & Schinz) Morrone & Zuloaga, U. brizantha (Hochst. ex A. Rich.) R.D. Webster, U. eminii (Mez) Davidse [listed as the synonym Brachiaria decumbens Stapf ], Urochloa mutica (Forssk.) T.Q. Nguyen, and U. trichopus (Hochst.) Stapf [listed as the synonym U. mosambicensis (Hack.) Dandy].

The weakest aspects of the descriptions previously published for these species (Camus, 1925, 1935, 1947, 1950, 1954, 1957; Clayton & Renvoize, 1982; Clayton et al., 2006; Bosser & Renvoize, 2018) were the data on field growth and habit, as Camus did not personally carry out field observations, and her herbarium-based descriptions were used to compile the later datasets. Creeping grasses of the forest understory such as Brachiaria bemarivensis A. Camus can appear to be annual on specimens while the same culms can in fact continue growing for multiple years, rooting at culm nodes. The descriptions presented here incorporate ten years of field observations made across Madagascar and present updates especially regarding the annual/perennial habit and growth form.

Please note that this is a temporary generic classification, an intermediate stage of the work to place Malagasy biodiversity into monophyletic genera; the genus “Brachiaria” represents species yet to receive their updated generic names.

Key to the species of Brachiaria s.l., Echinochloa p.p., Moorochloa, and Urochloa p.p. in Madagascar

1. Spikelets ≥ 3 mm long 2

1a. Spikelets < 3 mm long 17

2. Spikelets in a dense and tidy imbricate arrangement of evenly sized racemes; rhachis narrowly winged to broad and foliaceous, (0.5–)0.8–3.5 mm wide 3

2a. Spikelets not overlapping or overlapping untidily, racemes usually decreasing in length towards apex of synflorescence; rhachis narrow or triquetrous, < 0.8 mm wide (rarely narrowly winged up to 1 mm wide) 10

3. Lower glume turned away from rhachis, turned towards viewer and therefore visible on majority of spikelets; upper lemma rugulose, with a mucro 0.3–1.2 mm long 4

3a. Lower glume turned towards rhachis, turned away from viewer and not immediately visible on majority of spikelets; upper lemma smooth to rugulose, without or with a minute mucro 5

4. Lower glume ¼–⅓ as long as spikelet; spikelets acute, usually without a setose fringe 26. Urochloa panicoides

4a. Lower glume ⅔–¾ as long as spikelet; spikelets acuminate, usually with a prominent setose fringe 31. Urochloa trichopus

5. Spikelets 3–4 mm long 6

5a. Spikelets 4–6 mm long . 8

6. Rhachis margins with yellow bulbous based trichomes; lower glume ⅔–¾ as long as spikelet 23. Urochloa jubata

6a. Rhachis margins scaberulous or with translucent trichomes; lower glume ⅓–½ as long as spikelet 7

7. Spikelets 2.5–3.7 mm long; lower glume 5–7-veined; mostly prostrate plants of low elevations 19. Urochloadistachyos

7a. Spikelets 3.5–4 mm long; lower glume 3-veined; mostly erect plants of High Plateau 16. Urochloa arrecta

8. Rhachis scaberulous; spikelets not obviously plump, acute 27. Urochloa plantaginea

8a. Rhachis ciliate; spikelets plump and subacute 9

9. Rhachis 1–1.5 mm wide; upper glume and lower lemma cartilaginous, dully shining 17. Urochloa brizantha

9a. Rhachis 2–3.5 mm wide; upper glume and lower lemma membranous, not shining 20. Urochloa eminii

10. Spikelets with a prominent ciliate rim ⅔ from base, with dense white trichomes 1–2 mm long 9. Brachiaria subrostrata

10a. Spikelets with a no ciliate rim, glabrous to evenly pilose, with trichomes < 1 mm long 11

11. Lower glume ⅔ to as long as spikelet 12

11a. Lower glume up to ½ as long as spikelet 14

12. Spikelets dorsally compressed; glumes acuminate to mucronate 21. Urochloa glumaris

12a. Spikelets laterally compressed; glumes pinched at apices 13

13. Leaf blades linear or rolled, 3–6 mm wide; plants with no smell 1. Brachiaria antsirabensis

13a. Leaf blades lanceolate, 12–20 mm wide; plants scented 6. Brachiaria fragrans

14. Spikelets oblong; upper lemma smooth and shiny 10. Brachiaria tsiafajavonensis

14a. Spikelets ellipsoid; upper lemma rugulose to rugose 15

15. Stoloniferous perennials; leaf blades linear; spikelets arranged in several untidy rows 24. Urochloa mutica

15a. Loosely tufted annuals; leaf blades lanceolate; spikelets paired 16

16. At least some pedicels longer than spikelets 18. Urochloa deflexa

16a. All pedicels shorter than spikelets 29. Urochloa ramosa

17. Spikelets ≤ 2 mm long 18

17a. Spikelets > 2 mm long 24

18. Spikelets on a single raceme not overlapping, with gaps between 19

18a. Spikelets on a single raceme imbricate or overlapping, with no gaps between most spikelets 21

19. Lower glume absent or up to ⅔ of spikelet length, with no veins; leaf blades thickly chartaceous; spikelets single 11. Brachiaria umbellata

19a. Lower glume ½–⅔ as long as spikelet, 3-veined; leaf blades membranous to chartaceous; spikelets paired 20

20. Spikelets apically rounded, whiteish, usually > 15 per inflorescence; leaf blades 1–7 × 0.3–1 cm 2. Brachiaria bemarivensis

20a. Spikelets apically acute, green, ≤ 15 per inflorescence; leaf blades 0.5–1.5 × 0.1–0.45 cm 5. Brachiaria epacridifolia

21. Mat-forming plants not rising > 5 cm above ground level; ligule absent 14. Echinochloa serpens

21a. Plant with erect flowering culms; ligule present 22

22. Leaf blades linear; loosely tufted annuals with no stolons; spikelets tidily imbricate on evenly sized racemes 15. Moorochloa eruciformis

22a. Leaf blades lanceolate to elliptic or ovate; stoloniferous annuals or perennials; spikelets untidily overlapping on racemes, these decreasing in length going up synflorescence 23

23. Inflorescence 5–35 cm long; spikelets elliptic to oblong, apically rounded; upper lemma smooth with no mucro 3. Brachiaria comorensis

23a. Inflorescence 3–5 cm long; spikelets ovate, apically acute; upper lemma finely rugulose, mucronate 30. Urochloa reptans

24. Spikelets densely covered with white to pink trichomes, with short white trichomes in lower part and dense white to pink trichomes c. 2 mm long in upper third; lower lemma grooved and mucronate 8. Brachiaria perrieri

24a. Spikelets glabrous or evenly pubescent; lower lemma not grooved or mucronate 25

25. Lower glume ⅔–¾ as long as spikelet 26

25a. Lower glume minute or up to ⅔ as long as spikelet 29

26. Rhachis margins ciliate with yellow bulbous-based trichomes 23. Urochloa jubata

26a. Rhachis margins scaberulous or with linear translucent trichomes 27

27. Spikelets dorsally compressed; ligule absent 13. Echinochloa leandriana

27a. Spikelets laterally compressed; ligule a truncate membrane 28

28. Leaf blades linear, 3–7 cm long 1. Brachiaria antsirabensis

28a. Leaf blades lanceolate, 0.8–3 cm long 4. Brachiaria dimorpha

29. Spikelets within a single raceme not overlapping 30

29a. Spikelets within a single raceme overlapping or imbricate 34

30. Culms woody; plants resembling a miniature bamboo 7. Brachiaria fruticulosa

30a. Culms herbaceous; plants a mat forming, stoloniferous, or annual grasses 31

31. Spikelets plump, apiculate; upper lemma rugose 29. Urochloa ramosa

31a. Spikelets not obviously plump, apically rounded to subacute; upper lemma usually smooth, sometimes finely rugulose 32

32. Leaf blades membranous; lower glume ½–⅔ as long as spikelet 2. Brachiariabemarivensis

32a. Leaf blades chartaceous; lower glume ¼–⅓ as long as spikelet 33

33. Leaf blades 1–5 mm wide; open and partly closed canopy habitats in southern Madagascar < 800 m elevation 22. Urochloa humbertiana

33a. Leaf blades 6–12 mm wide; forest shade in central, northern, and eastern Madagascar at 650–2300 m elevation 10. Brachiaria tsiafajavonensis

34. Inflorescence capitate, with up to 15(–30) spikelets on each culm 12. Echinochloa hubbardii

34a. Inflorescence racemose, with > 15 spikelets on each culm 35

35. Racemes 1–2; plants sprawling branched at every node 28. Urochloa pseudodichotoma

35a. Racemes > 2; plants sprawling to erect, not branching at every node 36

36. Plants annual, with no stolons 37

36a. Plants perennial, stoloniferous or rarely annuals 38

37. Spikelets subsessile and tidily imbricate on appressed racemes 15. Moorochloa eruciformis

37a. Spikelets on pedicels of uneven length, partly overlapping, racemes divergent 29. Urochloa ramosa

38. Racemes 5–20; spikelets in several untidy rows 24. Urochloa mutica

38a. Racemes 2–7; spikelets in 2 rows or not arranged in rows 39

39. Leaf blades 6–12 mm wide; spikelets oblong; species of forests 10. Brachiaria tsiafajavonensis

39a. Leaf blades 3–7 mm wide; spikelets ellipsoid; species of open areas 40

40. Spikelets neatly imbricate 19. Urochloa distachyos

40a. Spikelets overlapping untidily 25. Urochloa nana

Taxonomic treatment

1. Brachiaria antsirabensis A. Camus in Bull. Soc. Bot. France 77: 640. 1931.

  • Lectotypus (designated here): Madagascar. Reg. Amoron'i Mania [Prov. Fianarantsoa]: env. d'Ambositra, 1500 m, I.1914, Perrier de la Bâthie 10758 (P [P00450157]!; isolecto-: K [K000244724 fragm.]!, P [P00450158]!).

  • Loosely tufted stoloniferous perennial, ascending to erect, to c. 30 cm high, culms weakly branched, wiry, glabrous. Leaf sheath glabrous or with ciliate margins. Ligule a truncate membrane. Leaf blade linear, flat or rolled, chartaceous, 3–7 × 0.3–0.6 cm, glabrous to pubescent on both sides, retrorse at maturity. Inflorescence racemose, often condensed, ascendent, 2–7 cm long, peduncle pubescent. Racemes 2–6, 0.5–1.5(–2.5) cm long, roughly even in length, on a common axis 1–5 cm long, with no secondary branching, rhachis narrow, ciliate, spikelets overlapping untidily with adjacent spikelets, single or paired, subsessile. Spikelets laterally compressed, ovate, apiculate, 2.7–3.3 mm long, olive green. Lower glume ⅔–¾ as long as spikelet, herbaceous, keeled, pinched at apex, 7-veined, glabrous to pubescent, orientation relative to rhachis variable. Upper glume ¾ as long as spikelet, herbaceous, 7-veined, glabrous to pubescent. Lower floret male, palea as long as lemma, anthers 3.2–2.3 mm long. Lower lemma herbaceous, 7-veined, glabrous to pubescent. Upper lemma acute, smooth, shiny, white to brown.

  • Distribution and ecology. – Endemic to open highland savanna with Loudetia simplex (Nees) C.E. Hubb. and secondary grassland in central Madagascar, often on rocky slopes, near ericoid vegetation, or under tapia, at elevations of 800–1800 m (Fig. 1).

  • Notes. – This distinctive species is easy to recognise by its dense untidy inflorescences of overlapping spikelets. It shares laterally compressed spikelets and short upper glumes with its closest relative Brachiaria dimorpha A. Camus, another highland endemic (Hackel et al., 2018). Not fire resistant (Perrier de la Bâthie 10758). Somewhat swollen stolons may act as food storage. Not common or locally abundant, does not seem to become ecologically dominant.

  • The specimen designated here as the lectotype [P00450157] has superior quality flowering material than the duplicates, and it has previously been labelled as the holotype.

  • Additional specimens examined. – Madagascar. Reg. Alaotra-Mangoro [Prov. Toamasina]: rte. de Moramanga-Lac Alaotra, PK 15, VI.1959, Bosser 13044 (P); sur le Mongoro, XII.1927, Perrier de la Bâthie 18344 (P). Reg. Amoron'i Mania [Prov. Fianarantsoa]: Fandriana, I.1953, Bosser 5073 (TAN); Marovitsika (Anjiro), XI.1953, Bosser 7135 (P); ibid. loco, III.1953, Bosser 7140 (TAN); Ambositra, Imerina-Imady, I.1961, Bosser 14884 (P); Faliarivo, env. d'Ambositra, III.1934, Humbert 14518 (P); 6 km from Ivato towards Ambatofinandrahana, 24.II.2013, Vorontsova et al. 992 (K, TAN). Reg. Analamanga [Prov. Antananarivo]: Ankazobe, Manerinerina, rte. de Majunga, PK 135, I.1967, Morat 2657[b] (P); entre Arivonimamo et Soamananety, 29.I.1960, Peltier 1826 (P). Reg. Itasy [Prov. Antananarivo]: Nanisana, 14.I.1951, Benoist 698 (P); ibid. loco, 14.I.1951, Benoist s.n. (P); Arivonimamo, Antongona, I.1956, Bosser 8933 (P, TAN); massif de l'Antongona, 4.XII.1959, Peltier & Peltier 1573 (P). Reg. Vakinankaratra [Prov. Antananarivo]: Ambatolampy, I.1953, Bosser 4748 (TAN); ibid. loco, II.1953, Bosser 4782 (TAN); ibid. loco, II.1953, Bosser 4810 (P, TAN); ibid. loco, II.1953, Bosser 5062 (TAN); Faratsiho, Ankaratra, I.1955, Bosser 7633 (P); Behenjy, Andosy, Cornet 13 (TAN); Amboasary (Behenjy), 28.XII.1963, Peltier 4517 (P). Sine loco: “Central Madagascar”, Baron 3713 (K, P).

  • 2. Brachiaria bemarivensis A. Camus in Bull. Soc. Bot. France 72: 369. 1925 (Fig. 2A–C).

  • Lectotypus (designated here): Madagascar. Reg. Boeny [Prov. Mahajanga]: Haute Bemarivo, II.1907, Perrier de la Bâthie 11295 (P [P00450163]!; isolecto-: P [P00450164, P00450165]!). Syntypus: ibid. loco, III.1907, Perrier de la Bâthie 11136 [as 11135] (P [P02040451, P02040452]!).

  • = Brachiaria bemarivensis subsp. ankarafantsikaensis A. Camus in Naturaliste Malgache 5: 147. 1953. Lectotypus (designated here): Madagascar. Reg. Boeny [Prov. Mahajanga]: Ankarafantsika près de Marovoay, III.1910, Perrier de la Bâthie 11223 (P [P00450162]!; isolecto-: P [P02040448, P00450167, P00450168]!). Syntypus: ibid. loco, III.1910, Perrier de la Bâthie 11225 (P [P00450160, P00450161, P00450166]!).

  • = Acroceras parvulum A. Camus in Bull. Soc. Bot. France 101: 28. 1954, syn. nov. Holotypus: Madagascar. Reg. Anosy [Prov. Toliara]: vallée du Mandrare, affl. de la Manampanihy, montagne au S de Tanandava, c. 500 m, III.1947, Humbert 20486 (P [P00450108]!).

  • = Brachiaria benoistii A. Camus in Bull. Soc. Bot. France 101: 28. 1954. Lectotypus (designated here): Madagascar.Reg.Atsinanana[Prov.Fianarantsoa]:env.d'Ambila,17.III.1951,Benoist813(P [P00450169]!). Syntypus: ibid. loco, 4.V.1928, Decary 6383 (P [P00450170!]).

  • Mat-forming annual to short-lived stoloniferous perennial, prostrate with ascending flowering culms, to 0.6 m high, culms branched, rooting at lower nodes, glabrous. Leaf sheath sparsely hirsute, sometimes with bulbous-based trichomes towards apex. Ligule a lacerate ciliolate membrane. Leaf blade ovate to elliptic, membranous, 1–7 × 0.3–1 cm, often tinged with purple, glabrous to sparsely hirsute on both sides, sometimes with bulbous-based trichomes at base. Inflorescence racemose, slender, open, 5–12 cm long. Racemes 1–10, 2–6 cm long, decreasing in length upwards, lowermost raceme roughly equal to inflorescence axis in length, on a common axis 0–7 cm long, sometimes with secondary branches, rhachis narrow, scaberulous, spikelets widely spaced paired, sessile and shortly pedicelled in each pair. Spikelets elliptic, apically rounded, 1.7–2.3 mm long, whiteish, sometimes tinged with purple. Lower glume ½–⅔ as long as spikelet, membranous, obtuse to acute, 3-veined, glabrous or with shiny elongated prickle hairs, with fine white trichomes at apex, orientation relative to rhachis variable. Upper glume as long as spikelet, membranous, 5-veined, glabrous or with shiny elongated pricke hairs, detaching early. Lower floret male, palea ½ as long as lemma, anthers 3, 0.7 mm long. Lower lemma membranous, 5-veined, glabrous or with shiny elongated prickle hairs. Upper lemma rounded, smooth, shiny, pale becoming brown at maturity, with a green apical crest.

  • Distribution and ecology. – Common across Madagascar except the arid west and southwest, in the shade, forest edges, and forest understory, on dunes, sand, rocks, and roadsides, at elevations of 0–1600 m (Fig. 1).

  • Notes. – This attractive, fragile creeping plant with membranous leaf blades forms common ground cover across much of Madagascar. Young foliage is often tinged with red. Plant size, leaf width, and inflorescence size vary considerably.

  • It seems that environmental stress can result in culms with a single raceme only, and these have been described as Brachiaria benoistii A. Camus and Acroceras parvulum A. Camus. These collections have a single main inflorescence axis and poorly developed racemes, and have been collected from the east coast. These are not recognised here as a distinct taxon because no differences other than the inflorescence structure have been observed.

  • In the protologue of Brachiaria bemarivensis, Camus cites two collection numbers from forests in Bemarivo: Perrier de la Bâthie 11135 and 11295. Perrier de la Bâthie 11135 is almost certainly a transcription error for 11136 corrected here: the handwritten numbers 5 and 6 appear similar on the sheets, and 11135 is a collection of Schizachyrium Nees. The chosen lectotype is the best quality sheet from the collection that lacks ambiguity. The respective lectotypes designated here for Brachiaria bemarivensis subsp. ankarafantsikaensis A. Camus [P00450163] and B. benoistii [P00450162] represent the best preserved material annotated by Camus.

  • The name “Brachiaria bemarivensis var. benoistii (A. Camus) Bosser” appears on some herbarium sheets held at P and annotated by Bosser (e.g. Benoist 813, P [P00450169]) but this name does not appear to have been published and is therefore an invalid name (nomen nudum in sched.).

  • Selected specimens examined. – Madagascar. Reg. Amoron'i Mania [Prov. Fianarantsoa]: Itremo, Andohatanimena, 19.II.2014, Nanjarisoa et al. 147 (K, TAN). Reg. Analamanga [Prov. Antananarivo]: Anjozorobe, Analabe, III.1952, Bosser 2408 (P); Tampoketsa d'Ankazobe, III.1962, Bosser 15985 (P); Belobaka, Analandraisoa, forêt d'Analandraisoa, IV.1963, Bosser 17650 (P). Reg. Analanjirofo [Prov. Toamasina]: Fenoarivo Est, XI.1954, Bosser & Descoings 78 (P); Mahavelona, XII.1962, Bosser 16869 (P); Maroantsetra, Nosy Mangabe, V.1988, Schatz et al. 2325 (MO, P, TAN). Reg. Anosy [Prov. Toliara]: Beroroha, vallée du Mandrare, affl. de la Manampanihy, S de Tanandava, 11.III.1947, Humbert 71 (P); Taolagnaro, Mahatalaky. Sainte Luce, 23.I.2012, Rakotonirina et al. 741 (P). Reg. Atsimo-Andrefana [Prov. Toliara]: Sakaraha, forêt du Zombitsy, III.1964, Bosser 19375 (P, TAN). Reg. Betsiboka [Prov. Mahajunga]: env. de Maevatanana, III.1900, Perrier de la Bâthie 1032 (P). Reg. Boeny [Prov. Mahajunga]: Ankarafantsika National Park office, 14.II.2017, Vorontsova & Duncan-Rice 2090 (K, P, TAN). Reg. DIANA [Prov. Antsiranana]: vallée de l'Ifasy en aval d'Anaborano, 31.III.1951, Humbert & Capuron 25898 (K, P); RS Manongarivo, Bekolosy, near village of Ambalafary, 12.III.1993, Malcomber et al. 2234 (MO, P); ibid. loco, 12.V.2014, Vorontsova & Onjalalaina 1470 (P, TAN). Reg. Ihorombe [Prov. Fianarantsoa]: plateaux et vallées de l'Isalo, 29.I.1955, Humbert 29811 (K, P). Reg. Fitovinany [Prov. Fianarantsoa]: env. d'Ambila, 17.III.1951, Benoist 813 (P).

  • Fig. 1.

    Distribution maps. Brachiaria antsirabensis A. Camus (stars), B. bemarivensis A. Camus (triangles), B. comorensis (Mez) A. Camus (circles), and B. dimorpha A. Camus (squares). [Map: Sarah Z. Ficinski]

    img-z5-10_199.jpg

    3. Brachiaria comorensis (Mez) A. Camus in Rev. Int. Bot. Appl. Agric. Trop. 27: 280. 1947 (Fig. 2D, 3).

  • Panicum comorense Mez in Bot. Jahrb. Syst. 57: 185. 1921.

  • Lectotypus (designated here): Tanzania. Reg. Tanga: Usambara, Mlalo, IV.1892, Holst 549 [459] (B [B 10 1037908] image!; isolecto-: B [B 10 1037909] image!, P [P00450172]!, US [US-80594 fragm.]!). Syntypus: Comoros. Grande Comore: sine loco, V.1850, Boivin s.n. (P [P00216299]!).

  • = Brachiaria capuronii A. Camus in Bull. Mus. Natl. Hist. Nat., sér. 2, 29: 278. 1957. Lectotypus (designated here): Madagascar. Reg. Atsimo-Andrefana [Prov. Toliara]: vallée de l'Hazoroa, bassin de l'Onilahy, au S de Sakaraha, 500–600 m, 30.III.1955, Humbert & Capuron 29688 (P [P00450171]!; isolecto-: MO, P [P03652846, P03652847]!).

  • = Brachiaria decaryana A. Camus in Bull. Mus. Natl. Hist. Nat., sér. 2, 29: 278. 1957. Lectotypus (designated here): Madagascar. Reg. Sofia [Prov. Mahajanga]: Ankaizinana, 1000 m, 27.IV.1923, Decary 2078 (P [P00450173]!; isolecto-: P [P00450174]!).

  • Annual to short-lived stoloniferous perennial, ascending, to 0.6 m high, culms weakly branched, rooting at lower nodes, glabrous. Leaf sheath glabrous to sparsely pubescent towards apex. Ligule a truncate membrane with no trichomes. Leaf blade elliptic, membranous, 2.5–15 × 0.5–1.3 cm, glaucous underneath, glabrous to sparsely pubescent on both sides. Inflorescence racemose, slender, often incompletely exserted in shade, 5–35 cm long. Racemes 5–20, 2–12 cm long, flexuous, decreasing in length upwards, lowermost raceme roughly equal to inflorescence axis in length, on a common axis 3–20 cm long, often with numerous secondary branches, rhachis narrow, scaberulous, spikelets overlapping untidily with adjacent spikelets, single, pedicels up to twice as long as spikelet. Spikelets elliptic to oblong, apically rounded, 1.5–1.8 mm long, whiteish with a green tinge, sometimes tinged with purple. Lower glume ¼–⅓ as long as spikelet, membranous, obtuse to acute, 1-veined, glabrous, clasping, orientation relative to rhachis variable. Upper glume as long as spikelet, membranous, 3-veined, veins raised, glabrous. Lower floret infertile, palea absent. Lower lemma membranous, 5-veined, veins raised, depressed between veins. Upper lemma obtuse, smooth, shiny, pale becoming brown at maturity.

  • Distribution and ecology. – West and eastern tropical Africa and the Comoro Islands. In Madagascar is common in low elevation and sometimes mid-elevation seasonal forest understory and shade, dry and seasonally wet habitats, in the north and south, at elevations of 0–800 m (Fig. 1).

  • Notes. – Superficially similar to Brachiaria bemarivensis due to shared broad membranous leaf blades and small white apically rounded spikelets, but can be reliably distinguished in a variety of ways: bulbous-based trichomes on leaf surfaces (versus leaf surfaces with linear trichomes in B. bemarivensis), spikelets overlapping (not with gaps between adjacent spikelets within a single raceme), lower glume ¼–⅓ of the spikelet length with a single vein (⅓–½ and with 3 veins), glumes and lower lemma smooth (with enlarged prickle hairs). Often seen sterile or with immature inflorescence emerging from leaf sheaths.

  • It is not clear why the African floras (Hutchinson & Dalziel, 1972; Clayton & Renvoize, 1982; Clayton, 1989) placed this species in the genus Panicum in spite of its clearly racemose inflorescences while Bosser (1969) omitted it altogether. Appears to be absent from Mauritius and La Reunion (Bosser & Renvoize, 2018). The first sequence analysis by Hackel et al. (2018) demonstrated that it is sister to the Malagasy forest endemic Brachiaria tsiafajavonensis A. Camus, see discussion under that species.

  • The lectotype of Panicum comorense Mez at B [B 10 1037908] designated here is the best preserved material seen by Mez. The correct collection number seems to be Holst 549, although the second duplicate at B and the fragment at US are labelled as Holst 459.

  • Selected specimens examined. – Madagascar. Reg. Alaotra-Mangoro [Prov. Toamasina]: lac Alaotra (S-169), Jard. Bot. Tananarive 3407 (P). Reg. Atsimo-Andrefana [Prov. Toliara]: plateau Mahafaly à l'W de Betioky, III.1955, Humbert & Capuron 29445 (K, MO, P, TAN); PK 32, rte. pour Ifaty, 21.IV.2014, Nanjarisoa et al. 193 (K, TAN); Beza Mahafaly Reserve, parcelle 1, 13.II.1990, Phillipson 3486 (K, P). Reg. Betsiboka [Prov. Mahajanga]: bois Firingalava, III.1898, Perrier de la Bâthie 552 (P). Reg. Boeny [Prov. Mahajanga]: Ambato-Boeni, bassin supérieur de Bemarivo, III.1907, Perrier de la Bâthie 11245 (P). Reg. Bongolava [Prov. Antananarivo]: Sakay, 1.I.1970, Bosser 20264 (P). Reg. DIANA [Prov. Antsiranana]: Daraina, forêt de Bekaraoka, Andranotsimaty, 13.III.2003, Gautier et al. 4359 (G, P); Ambanja, Befalafa, moyen Ambahatra, cours moyen du Bassin-versant, 2.V.1999, Wohlhauser & Andriamalaza 60086[b] (G, P); Ambahatra cours moyen, plateau d'Anketraka Be, 8.V.2000, Wohlhauser 60254 (G, K, P). Reg. Ihorombe [Prov. Fianarantsoa]: Parc National Isalo, Canyons des Singes, 25.IV.2018, Rakotomalala et al. 160 (K, P, TAN). Reg. Sofia [Prov. Mahajanga]: Bealanana, Ambatoria, Ankaizina, V.1952, Bosser 2661 (P).

  • Fig. 2.

    A–C. Brachiaria bemarivensis A. Camus; D. Brachiaria comorensis (Mez) A. Camus; E, F. Brachiaria dimorpha A. Camus. [A: Vorontsova et al. 1012; B, C: Vorontsova et al. 1770; D: Morris et al. 3; E, F: Nanjarisoa et al. 73] [Photos: Maria S. Vorontsova]

    img-z7-1_199.jpg

    Fig. 3.

    Brachiaria comorensis (Mez) A. Camus. A. Habit; B. Ligule; C. Panicle; D. Panicle branch; E. Spikelet; F. Lower glume, ventral view; G. Upper glume, ventral view; H. Lower lemma, ventral view; I. Upper floret, ventral view; J. Upper floret, lateral view; K. Upper lemma, ventral view; L. Upper lemma, dorsal view; M. Upper palea, ventral view; N. Upper palea, dorsal view. Scale bars: A, C = 3 cm; B = 3.3 mm; D = 2.5 mm; E–N = 0.8 mm. [A–C, E–N: Wohlhauser 60254, K; D: Nanjarisoa et al. 193, K] [Drawing: Lucy T. Smith]

    img-z8-1_199.jpg

    4. Brachiaria dimorpha A. Camus in Bull. Soc. Bot. France 72: 621. 1925 (Fig. 2E–F, 4).

  • Lectotypus (designated here): Madagascar. Reg. Ihorombe [Prov. Fianarantsoa]: massif d'Andringitra, 2000 m, I.1923, Perrier de la Bâthie 14333A et B [14333] (P [P03124753]!; isolecto-: K [K000244728]!, P [P03124768, P03124773]!). Syntypi: ibid. loco, 2400 m, II.1922, Perrier de la Bâthie 14333A (P [P03124774]!); ibid. loco, 2300 m, II.1922, Perrier de la Bâthie 14333B (P [P01973887]!).

  • Stoloniferous mat-forming perennial, prostrate with ascending flowering culms, to 10–40 cm high, culms branched, rooting at nodes, glabrous. Leaf sheath glabrous or sparsely pubescent. Ligule a truncate membrane. Leaf blade lanceolate, thickly chartaceous, 0.8–3 × 0.1–0.4 cm, glabrous to pubescent on both sides. Inflorescence racemose, slender, contracted, 1.5–10 cm long. Racemes 1–5, 0.3–3 cm long, much shorter than inflorescence axis, appressed, on a common axis 1–9 cm long, with no secondary branching, rhachis narrow, glabrous, spikelets overlapping with adjacent spikelets, paired, subsessile, on pedicels of uneven length. Spikelets somewhat laterally compressed, ovate, apically acute, 2.3–2.7 mm long, light green to purple. Lower glume ⅔–¾ as long as spikelet, membranous, keeled, acute to apiculate, 3–7-veined, glabrous to scaberulous, orientation relative to rhachis variable. Upper glume almost as long as spikelet, membranous, 3–5-veined, glabrous to sparsely pubescent. Lower floret male, palea as long as lemma, anthers 3, c. 1.5 mm long. Lower lemma membranous, 5-veined, glabrous to sparsely pubescent. Upper lemma acute, smooth, shiny, white to brown.

  • Distribution and ecology. – Endemic to the mountains of south-eastern Madagascar, open grassland and ericoid vegetation on rocks and by the sides of streams, peaty areas, often on gneiss, in areas protected from fire, at elevations of 1500–2500 m (Fig. 1).

  • Notes. – Brachiaria dimorpha is a distinctive species forming dense, almost moss-like cushions of vegetation with short erect inflorescences in open high elevation areas. This compact morphology changes in the shade under thickets of Erica L. to produce long leafy shoots. It is abundant and sometimes dominant on the 2000 m plateau of the Andringitra National Park. This species is shorter and grows at higher elections than its only known relative B. antsirabensis A. Camus, which shares its laterally compressed spikelets with short upper glumes.

  • There has been some confusion with the numbering of the original material by Perrier de la Bâthie. The protologue lists collections from three elevation ranges: up to 2000 (14333), 2300 (14333B), and 2400 (14333A). According to the label of P03124773 the numbers A and B were originally used by Perrier de la Bâthie to distinguish the plants he judged to be perennial (A) and annual (B). Herbarium sheets labels have three or four different numbers: 14333A [P03124774], 14333B [P01973887], 14333A et B [P03124753, P03124768, P03124773], and 14333 (duplicate outside P with the same data as A et B). The A and B sheets are annotated with the date February 1922, while A et B are annotated with January 1923 so it is possible that Perrier de la Bâthie later concluded that no distinction can be made between the annual and perennial plants. The lectotype designated here [P03124753] is already labelled as type, has the most comprehensive material, and is labelled as A et B. The original material is here interpreted as three different collection numbers characterised by the three different elevations, following the protologue.

  • Selected specimens examined. – Madagascar. Reg. Anosy [Prov. Toliara]: massif de l'Andohahela; vallée supérieure de la Sakamalio, I.1934, Humbert 13565 (P). Reg. Ihorombe [Prov. Fianarantsoa]: Sud-Andringitra, Andrianony, Manjarivolo, 2.XI.1970, Guillaumet 3491 (P); pic d'Ivohibe, XI.1924, Humbert 3311 (P); Massif de l'Andringitra, vallées de la Riambava et de l'Antsifotra, 27.XI.1924, Humbert 3697 (K, P); Andringitra NP, plateau E of camp 3, 13.XII.2013, Vorontsova et al. 1258 (K, TAN). Reg. Vakinankaratra [Prov. Antananarivo]: massif de l'Ibity, VI.1968, Morat 2862 (P).

  • Fig. 4.

    Brachiaria dimorpha A. Camus. A. Habit; B. Ligule; C. Panicle branch; D. Spikelet; E. Lower glume, ventral view; F. Lower glume, dorsal view; G. Upper glume, ventral view; H. Upper glume, dorsal view; I. Lower lemma, ventral view; J. Lower lemma, dorsal view; K. Lower palea, ventral view; L. Lower palea, dorsal view; M. Lower floret lodicule; N. Lower floret stamens; O. Upper floret, ventral view; P. Upper lemma, ventral view; Q. Upper lemma, dorsal view; R. Upper floret, after removal of the lemma; S. Upper palea, dorsal view. Scale bars: A = 3 cm; B = 2.5 mm; C = 3.3 mm; D–S = 1.5 mm. [Nanjarisoa et al. 82, K] [Drawing: Lucy T. Smith]

    img-z10-1_199.jpg

    5. Brachiaria epacridifolia (Stapf) A. Camus in Bull. Mus. Natl. Hist. Nat., sér. 2, 22: 297. 1950.

  • Panicum epacridifolium Stapf in Bull. Misc. Inform. Kew 1919: 266. 1919.

  • Lectotypus (designated here): Madagascar. Reg. Vakinankaratra [Prov. Antananarivo]: cîme au N d'Ambana, près d'Antsirabe, Ankaratra, rocailles, III.1912, 2000 m, Perrier de la Bâthie 11160 [80] (K [K000805466]!; isolecto-: P [P00450175, P02022202]!). Syntypus: Madagascar: “Central Madagascar”, s.d., Baron 4318 (K [K000244698]!, P [P00450176 fragm.]!).

  • = Brachiaria epacridifolia var. glabra A. Camus in Bull. Mus. Natl. Hist. Nat., sér. 2, 22: 297. 1950. Lectotypus (designated here): Madagascar. Reg. Analamanga [Prov. Antananarivo]: Analabe au N de Tananarive, 1500 m, II.1928, Perrier de la Bâthie 18437 (P [P01973847]!; isolecto-: P [P01973859]!). Syntypus: Madagascar. Reg. Vakinankaratra [Prov. Antananarivo]: Ankaratra, 2000 m, XII.1920, Perrier de la Bâthie 13384 (P [P01973848]!).

  • Stoloniferous mat-forming perennial, prostrate with ascending flowering culms, to 10 cm high, culms much branched, rooting at nodes, glabrous. Leaf sheath glabrous to pubescent. Ligule a miniscule truncate membrane. Leaf blade lanceolate to ovate, chartaceous, 0.5–1.5 × 0.1–0.45 cm, glabrous to pubescent on both sides. Inflorescence racemose, slender, open, 2–10 cm long. Racemes 1–6, 1–5 cm long, decreasing in length upwards, retrorse at maturity, on a common axis 0.5–6 cm long, with no secondary branching, rhachis narrow, glabrous, spikelets not overlapping with adjacent spikelets, paired, on pedicels of uneven length, rarely more than 15 spikelets per synflorescence. Spikelets ovate, apically acute, c. 2 mm long, dark green. Lower glume ½–⅔ as long as spikelet, membranous, acute, 3-veined, glabrous to finely scaberulous or verucculose at maturity, orientation relative to rhachis variable. Upper glume as long as spikelet or slightly shorter, membranous, 5-veined, glabrous to finely scaberulous or verucculose at maturity. Lower floret infertile, palea absent. Lower lemma membranous, 5-veined, glabrous to finely scaberulous or verrucculose at maturity. Upper lemma acute, smooth, shiny, white to yellowish.

  • Distribution and ecology. – Malagasy endemic restricted to northern, central, and south-eastern highlands, in humid and gallery forest shade and also open areas, on rocks, ericoid vegetation, sides of streams, and secondary vegetation, on laterite, gneiss, and clay, at elevations of 1300–2200 m (Fig. 5).

  • Notes. – Brachiaria epacridifolia (Stapf) A. Camus is easy to recognise by its distinctive, tidy branches and spikelets, short and somewhat retrorse racemes at maturity, and its cushion habit. Its inflorescences are often poorly developed without clear racemes, justifying an alternative placement in the genus Panicum under a morphological classification system. It is commonly seen in shady forest understory and near forest edges. The mature inflorescences of B. epacridifolia somewhat resemble those of Trichanthecium parvifolium (Lam.) Zuloaga & Morrone but its spikelets are less rounded, and the plant is not glaucous.

  • The lectotype of Brachiaria epacridifolia designated here [K000805466] is the best preserved original material with notes in Stapf's hand. Many of Perrier de la Bâthie's duplicates at K lack the five-digit collection numbers corresponding to those at P but are instead annotated with a different series of two-digit “provisional” numbers. For the chosen lectotype its numbers from both series are cited, with the provisional Kew number given in square brackets. None of the original material found for B. epacridifolia var. glabra A. Camus bears any note of this varietal epithet on the sheet; the lectotype designated here [P01973847] is annotated as Panicum epacridifolium Stapf in Camus' handwriting.

  • Selected specimens examined. – Madagascar. Reg. Alaotra-Mangoro [Prov. Toamasina]: Lac Alaotra, Jard. Bot. Tananarive 3425 (P). Reg. Analamanga [Prov. Antananarivo]: mont Angavokely, VI.1947, Humbert 20844 (K, P); Ankazobe, Ankafobe, endophyte plot AN30, VI.2016, Vorontsova et al. 1923 (K, TAN). Reg. Anosy [Prov. Toliara]: massif du Kalambatitra, mont Analatsitendrika, XI.1933, Humbert 11922 (P); mont Itrafanaomby, XII.1933, Humbert 13484 (P). Reg. Amoron'i Mania [Prov. Fianarantsoa]: Itremo, Ambatoantrano, III.2014, Nanjarisoa et al. 129a (K, TAN). Reg. DIANA [Prov. Antsiranana]: massif du Tsaratanana, plateaux supérieurs et hauts sommets de l'Amboabory à l'Antsianongatalata, XI.1937, Humbert 18373bis (P); montagnes au N de Mangindrano; jusqu'aux sommets d'Ambohimirahavavy, XI.1951, Humbert & Capuron 25292 (P). Reg. Haute Matsiatra [Prov. Fianarantsoa]: Andringitra National Park, VI.1965, Morat 1304 (P). Reg. Sofia [Prov. Mahajanga]: Tsaratanana Reserve, Misorobe, walking from camp 2 towards camp 1 and Mangindrano, XI.2017, Vorontsova et al. 2113 (K, MO, P, TAN). Reg. Vakinankaratra [Prov. Antananarivo]: Ankaratra, au dessus de Manjakatompo, III.1961, Bosser 15277 (P). Reg. Vatovavy [Prov. Fianarantsoa]: Ranomafana, Ifanadiana, I.1964, Bosser 18779 (P).

  • Fig. 5.

    Distribution maps. Brachiaria epacridifolia (Stapf) A. Camus (stars), B. fragrans A. Camus (triangles), B. fruticulosa A. Camus (circles), and B. perrieri A. Camus (squares).

    img-z12-1_199.jpg

    6. Brachiaria fragrans A. Camus in Bull. Soc. Bot. France 82: 22. 1935 (Fig. 6).

  • Lectotypus (designated here): Madagascar. Reg. Atsimo-Andrefana [Prov. Toliara]: plateau calcaire au N du Fiherenana, forêt sèche de Fandrare à 40 km NE de Tulear, 400 – 700 m, III.1934, Humbert 14315 (P [P00450177]!; isolecto-: K [K00024472]!, P [P00450178, P00450179]!).

  • Stoloniferous perennial, ascending, to 2 m high, culms not branched, rooting at lower nodes, with a knotty rootstock, glabrous. Leaf sheath glabrous with ciliate margins. Ligule a ciliolate membrane. Leaf blade lanceolate, basally asymmetric and often cordate on one side, chartaceous, 8–18 × 1.2–2 cm, glaucous underneath, glabrous on both sides, often with bulbous-based trichomes near base. Inflorescence racemose, contracted, rarely fully exserted, 5–10 cm long. Racemes 3–4, 1–3.5 cm long, decreasing in length upwards, on a common axis 2–8 cm long, with no secondary branching, rhachis narrow, scaberulous, spikelets overlapping untidily with adjacent spikelets, paired, on pedicels of uneven length. Spikelets laterally compressed, ovate, apically acute, 3.5–4 mm long, white. Lower glume c. ⅔ as long as spikelet, chartaceous, (3–)5-veined, scaberulous, thick keel developing into a small apical wing, orientation relative to rhachis variable. Upper glume ¾ as long as spikelet, chartaceous, 5-veined, scaberulous, pinched at apex. Lower floret male, palea as long as lemma, anthers 3, c. 2.5 mm long. Lower lemma chartaceous, 5-veined, scaberulous, pinched at apex. Upper lemma acute, matte, smooth but not shiny, with an apical crest and minute trichomes at apex.

  • Distribution and ecology. – Endemic to the understory of seasonally dry forest and scrub to the north of Toliara, on rocks and limestone soils, at elevations of 30–700 m (Fig. 5).

  • Notes. – Brachiaria fragrans A. Camus seems to possess a property rarely seen in the Poaceae: an odour. On P03175998, Camus noted: “plante très intéressante découverte par le Professeur Humbert à 40 km, de Tulear, au N de Fiherenana, sur le calcaire. Fleurs assez odorantes [a very interesting plant discovered by Professor Humbert 40 km from Tulear, to the N of Fiherenana, on limestone. Quite fragrant flowers]” while the type collection labels cite “fleurs à fine odeur de Lis! [flowers with a fine scent of lily!]” This mysterious species was not found in the wild during several expeditions searching for it conducted by the author.

  • The closest relatives of Brachiaria fragrans in the Boivinellinae (Appendix) are also unusual Malagasy endemics. The only related species bearing some morphological resemblance it is B. bemarivensis, also a broad-leaved grass with spikelets that look white when fresh. The spikelets of B. fragrans are significantly larger, however, and resemble the genus Acroceras Stapf with their pinched upper glume and lower lemmas, and a crested upper lemma. Brachiaria fragrans differs from Acroceras ivohibense A. Camus by its white (not brown) spikelets and partly (not fully) exerted inflorescences.

  • Additional specimens examined. – Madagascar. Reg. Atsimo-Andrefana [Prov. Toliara]: 50 km de Tulear, rte. de Sakaraha, III.1960, Bosser 14058 (P); rte. Tulear PK 55, III.1964, Bosser 19160 (P); Toliara ville, vallée du Fiherenana, XI.1933, Humbert 11587 (P); gorges du Fiherenana entre Beantsy et Anjamala, I.1947, Humbert 19919 (P); gorges de la Manombo, I.1947, Humbert 19972 (P); Morombe, 15 km de Befandriana, 5.IV.1955, Humbert 29739 (P); à 50 km de Tulear, rte. Tulear à Sakaraha, III.1960, Keraudren-Aymonin 751 (P).

  • Fig. 6.

    Brachiaria fragrans A. Camus. A. Habit; B. Ligule; C. Panicle branch; D. Spikelet; E. Lower glume, ventral view; F. Lower glume, dorsal view; G. Upper glume, ventral view; H. Upper glume, dorsal view; I. Spikelet, glumes removed; J. Lower lemma, ventral view; K. Lower lemma, dorsal view; L. Lower floret lodicule; M. Lower palea, ventral view; N. Lower palea, dorsal view; O. Lower floret stamen; P. Upper floret, ventral view; Q. Upper floret, lateral view; R. Upper lemma, ventral view; S. Upper lemma, dorsal view; T. Upper palea, ventral view; U. Upper palea, dorsal view; V. Upper floret stamen; W. Upper floret gynoecium. Scale bar: A = 3 cm; B = 3.3 mm; C = 4 mm; D–W = 1.6 mm. [Humbert 14315, K] [Drawing: Lucy T. Smith]

    img-z13-1_199.jpg

    7. Brachiaria fruticulosa A. Camus in Bull. Mus. Natl. Hist. Nat., sér. 2, 29: 276. 1957.

  • Lectotypus (designated here): Madagascar. Reg. Anosy [Prov. Toliara]: Mont Ankazovandamena, près de la Baie des Galions (Ronofotsy) au SW de Fort-Dauphin, 100–450 m, 21.II.1955, Humbert & Capuron 29066 (P [P02344007]!; isolecto-: P [P02344004, P02344009]!).

  • Loosely tufted perennial, scrambling or erect, to 2 m high, culms woody, branched, resembling a bamboo, glabrous. Leaf sheath glabrous or hirsute with ciliate margins. Ligule a truncate membrane, with a tissue rim and a line of cilia outside of leaf. Leaf blade narrow-lanceolate, chartaceous, 2–7 × 0.3–0.7 cm, glabrous on both sides. Inflorescence racemose, slender, open, difficult to see among branches, 5–8 cm long. Racemes 2–4, 1–5 cm long, decreasing in length upwards, on a common axis 1–5 cm long, with no secondary branching, rhachis narrow, smooth or minutely scaberulous, spikelets not overlapping with adjacent spikelets, single or paired, on pedicels of uneven length. Spikelets elliptic, apically obtuse, 2.5–2.8 mm long, whiteish. Lower glume ⅓ as long as spikelet, membranous, obtuse, 3-veined, scaberulous towards apex, with hyaline margins, the orientation relative to rhachis variable. Upper glume as long as spikelet, membranous, 5-veined, scaberulous towards apex, with an apical crest. Lower floret infertile, palea absent. Lower lemma chartaceous, 5-veined, scaberulous. Upper lemma acute, smooth with minute trichomes towards apex, shiny, pale, with a green apical crest.

  • Distribution and ecology. – Known from the type only, southeastern Madagascar, seasonal forest shade on gneiss, at elevations of 100–450 m (Fig. 5).

  • Notes. – This mysterious species does not seem to have been seen again after the sole collection event in 1955. While the inflorescences have some superficial resemblance to the Malagasy highland endemic Panicum andringitremse A. Camus, the hard woody knotted rootstock, and the bamboo-like branching structure do not bear clear resemblance to any other species. No original field notes are available but the specimens suggest a small bamboo-like habit, partly erect and partly scrambling in shade over rocks, perhaps similarly to Oldeania ibityensis (A. Camus) D.Z. Li et al. Without the availability of DNA sequences it is difficult to be confident of its origins and taxonomic placement. The spikelet structure marks it clearly as a member of the tribe Paniceae, most likely the Boivinellinae, perhaps affiliated with the other bamboo-like scramblers in the genus Pseudolasiacis (A. Camus) A. Camus, although Pseudolasiacis are larger plants with bigger leaf blades and inflorescences, known from higher elevation habitats.

  • The lectotype designated here [P02344007] has the best preserved material and is annotated by Camus.

  • 8. Brachiaria perrieri A. Camus in Bull. Soc. Bot. France 77: 639. 1931.

  • Holotypus: Madagascar. Reg. Haute Matsiatra [Prov. Fianarantsoa]: près d'Ambalavao, 800 m, VIII.1923, Perrier de la Bâthie 14438 (P [P00450187]!; iso-: P [P00450188]!).

  • Loosely tufted annual, erect, 10–45 cm high, culms not branched, sometimes rooting at lower nodes, pubescent, nodes bearded. Leaf sheath pubescent. Ligule a line of hairs. Leaf blade ovate, chartaceous, 1–4 × 0.3–1.3 cm, densely pilose on both sides. Inflorescence racemose, slender, contracted, 3–6 cm long. Racemes 5–12, 1–1.8 cm long, roughly even in length, appressed, on a common axis 1.5–5 cm long, with no secondary branching, rhachis narrow, ciliate, spikelets overlapping with adjacent spikelets, single, subsessile, in 2 rows. Spikelets ovate, apically acute, 2–3 mm long, densely covered with white to pink trichomes. Lower glume c. ⅔ as long as spikelet, membranous, acute, 3-veined, densely pilose with white cilia, turned towards rhachis. Upper glume almost as long as spikelet, herbaceous, apiculate, 5-veined, veins poorly visible, with short white trichomes in lower part and dense white to pink trichomes c. 2 mm long in upper third. Lower floret male, palea as long as lemma. Lower lemma herbaceous, grooved, with a mucro c. 0.5 mm, 5-veined, veins poorly visible, pilose with sparse white trichomes in lower part and dense pink trichomes c. 2 mm long in upper part. Upper lemma apiculate, minutely striate.

  • Distribution and ecology. – Occurs across the central and southern part of the highlands, sometimes further south, on inselbergs and rocky slopes often associated with Styppeiochloa De Winter, commonly found on open wet rock after the rains, at elevations of 800–1500 m (Fig. 5).

  • Notes. – Attractive plant tinged with pink, and an easy to recognise endemic species. All collections have been made in the rainy period between January and March. Related to the endemic genus Yvesia A. Camus.

  • The sheet P00450187 is considered here as the holotype because it is labelled as “type” in Camus' hand and there is no evidence that he used the duplicate for describing the new species.

  • Selected specimens examined. – Madagascar. Reg. Androy [Prov. Toliara]: Ampandrandava entre Bekily et Tsivory, III.1943, Seyrig 565 (P). Reg. Haute Matsiatra [Prov. Fianarantsoa]: environs d'Ambalavao, II.1956, Bosser 8998 (P); Isorana, II.1961, Bosser 15180 (P); rte. Ambalavao-Ihosy PK 543, II.1963, Bosser 17875 (P); Ambalavao, Iarintsena, Tananomby, 15.III.2010, Rakotoarivelo et al. 225 (MO, P). Reg. Ihorombe [Prov. Fianarantsoa]: entre Ambalavao et Ihosy PK 547, II.1962, Bosser 15630 (P); S du radier d'Ampandrabe, Horombe, II.1965, Morat 2127 (P); Horombe plateau, II.1967, Morat 2646 (P); mont Belamboany, III.1912, Perrier de la Bâthie 11919 (P); Bonnet du Pape, RN 7, 22.III.2010, Ramandimbisoa et al. 130 (MO, P). Reg. Itasy [Prov. Antananarivo]: PK 23 rte. de Arivonimamo, I.1957, Bosser 10665 (P); Arivonimamo, Andranomena, 12.III.2011, Ramahefaharivelo 396 (MO, P).

  • 9. Brachiaria subrostrata A. Camus in Bull. Soc. Bot. France 73: 691. 1927 (Fig. 7, 8A–B).

  • Lectotypus (designated here): Madagascar. Reg. Vakinankaratra [Prov. Antananarivo]: Betafo, bords de chemins, 1200 m, III.1920, Perrier de la Bâthie 13064 (P [P00450190]!; isolecto-: K [K000244725, K000244726]!, P [P00450191, P00450192]!). Syntypus: Madagascar. Reg. Analamanga [Prov. Antananarivo]: Tananarive, III.1921, Perrier de la Bâthie 13661 (P [P01914074, P00450193, P00450194, P00450195]!).

  • Stoloniferous mat-forming perennial, prostrate with ascending flowering culms, to 7–10 cm high, culms branched at base, rooting at lower nodes, glabrous, nodes bearded. Leaf sheath pilose. Ligule a line of hairs. Leaf blade narrowly lanceolate, chartaceous, 1.5–7 × 0.3–0.7 cm, pilose on both sides. Inflorescence racemose, subcapitate, on a pilose peduncle, 1.5–3.5 cm long. Racemes 2–5, 0.5–2 cm long, appressed, decreasing in length upwards, on a common axis 0.5–2 cm long, with no secondary branching, rhachis triquetrous, scaberulous with some long cilia, spikelets overlapping untidily with adjacent spikelets, single or paired, on pedicels of uneven length. Spikelets obovate, apically acuminate, 3–3.5 mm long, green, with a prominent ciliate rim ⅔ from base. Lower glume c. ¼ as long as spikelet, membranous, rounded to acute, with no venation, glabrous to pubescent, orientation relative to rhachis variable. Upper glume as long as spikelet, herbaceous, long-acuminate, 5–7-veined, veins green and prominent, with cross veins near apex, with short white trichomes in lower part and dense white trichomes 1–2 mm long on the rim. Lower floret infertile, palea c. ⅓ as long as spikelet. Lower lemma herbaceous, long-acuminate, 5-veined, with short white trichomes in lower part and dense white trichomes 1–2 mm long on rim. Upper lemma obtuse, minutely striate.

  • Distribution and ecology. – Common component of moist highland roadside grazing lawns. Known only from lawns, grazed or otherwise physically disturbed open ecosystems, hence associated with human habitation, at elevations of 1200–1600 m (Fig. 9).

  • Notes. – Range restricted but commonly encountered aesthetically appealing species easily recognisable by a ciliate rim clearly visible on the apical parts of its spikelets. The spikelets detach as a single unit just below the glumes, and the spread-out cilia are likely involved in the seed dispersal process (Fig. 7, 8A–B).

  • The morphology of Brachiaria subrostrata A. Camus is fairly similar to its closest relatives in the chloroplast marker phylogeny by Hackel et al. (2018): the abundant B. umbellata (Trin.) Clayton with glabrous spikelets, and the annual Yvesia madagascariensis A. Camus. These are likely to fall in the same clade as the rare endemic annual Brachiaria perrieri A. Camus, which also has attractive long cilia on its spikelets, in common with B. subrostrata and Yvesia madagascariensis. Brachiaria subrostrata roots at the nodes and seems to flower early on in its life cycle, and is also frequently recorded as annual. These four species could potentially be assigned to a new genus once thorough sampling of continental African Brachiaria is added to the analyses.

  • The lectotype is selected for its best quality flowering material and broadest duplicate distribution. The syntype collection Perrier de la Bâthie 13661 bears an original note “probablement d'introduction récente” which likely reflects Perrier's erroneous assumption that roadside plants are not native. It is not included in his inventory of plants introduced to Madagascar (Perrier de la Bâthie, 1931, 1932), and is acknowledged as endemic by both Camus (1927) and Bosser (1969).

  • Selected specimens examined. – Madagascar. Reg. Analamanga [Prov. Antananarivo]: rte. de Manankavaly, III.1959, Bosser 12860 (P); env. de Tananarive, PK 13 rte. de Tamatave, II.1969, Bosser 19298 (P); Antananarivo centre, V.1903, Perrier de la Bâthie 15805 (P); Tzimbazaza, outside the herbarium building, 22.II.2013, Vorontsova & Besnard 988 (K, TAN); Antananarivo-ville, I.1916, Waterlot s.n. (P). Reg. Vakinankaratra [Prov. Antananarivo]: Manandona, 2.V.2014, Nanjarisoa et al. 218 (K, TAN); Antsirabe II, Vinanikarena village, 5.III.2017, Solofondranohatra et al. 803 (K, P, TAN); Ambohimandroso, Analamahitsy village, 26.IV.2017, Solofondranohatra et al. 884 (K, P, TAN); road to Ibity PA from Antsirabe, 28.II.2019, Vorontsova et al. 2397 (K, TAN).

  • 10. Brachiaria tsiafajavonensis A. Camus in Bull. Soc. Bot. France 72: 622. 1925 (Fig. 10).

  • Lectotypus (designated here): Madagascar. Reg. Vakinankaratra [Prov. Antananarivo]: mont Tsiafajavona, forêt, 2000 m, V.1922, Perrier de la Bâthie 14717 (P [P00450196]!; isolecto-: P [P00450197]!).

  • Stoloniferous mat-forming perennial, prostrate with ascending flowering culms, to 0.5 m high, culms weakly branched, rooting at lower nodes, glabrous. Leaf sheath glabrous to hirsute. Ligule a truncate membrane. Leaf blade lanceolate, chartaceous, 4–16 × 0.6–1.2 cm, glabrous to hirsute on both sides. Inflorescence racemose, slender, contracted, 10–20 cm long. Racemes 3–7, 3–10 cm long, flexuous, appressed, decreasing in length upwards, on a common axis 5–15 cm long, frequently with short secondary branches, rhachis narrow, scabrous and sometimes pubescent, spikelets overlapping with adjacent spikelets near base of synflorescence, single, on pedicels of uneven length. Spikelets oblong, apically subacute, 2.8–3.5 mm long, whiteish. Lower glume c. ¼ as long as spikelet, membranous, obtuse to acute, 1–3-veined, glabrous separated from rest of spikelet by an internode c. 0.25 mm long, orientation relative to rhachisvariable. Upper glume as long as spikelet, herbaceous, 5-veined, veins dark green, glabrous. Lower floret infertile, palea ⅓–½ as long as lemma. Lower lemma herbaceous, 5-veined, glabrous. Upper lemma obtuse to acute, smooth, shiny, pale, with apical green crest and some trichomes.

  • Distribution and ecology. – Madagascar endemic occurring in the central highlands, northern, and eastern areas, in the shade under mature wet mid-elevation and montane forest, often associated with isolated forest fragments, on gneiss and clay, at elevations of 650–2300 m (Fig. 9).

  • Notes. – Brachiaria tsiafajavonensis is a fairly common species of upland wet forest understory recognised by its oblong spikelet shape as well as its wide leaf blades. Forms with dark purple stripes across the spikelets are sometimes found. It differs from the southern low elevation species B. humbertiana A. Camus by its fully smooth upper lemma, plant rooting at lower nodes, and lower glume only ¼ of the spikelet length, as well as the internode between the glumes shorter than that of B. humbertiana. The plastid DNA regions analysed by Hackel et al. (2018) indicate a close relationship with the drier habitat species B. comorensis (Mez) A. Camus, with similarly broad leaf blades, and elliptic-oblong spikelets, glumes shorter than ⅓ of the spikelet length, and smooth upper lemmas.

  • Selected specimens examined. – Madagascar. Reg. Alaotra-Mangoro [Prov. Toamasina]: Mantadia NP, Tsakoka trail, 16.III.2016, Vorontsova et al. 1856 (K, P, TAN); Mantadia NP, c. 1 km past the entrance to the Chute Sacrée, 5.VIII.2019, Vorontsova et al. 2403 (K, TAN). Reg. Amoron'i Mania [Prov. Fianarantsoa]: env. D'Ambositra, mont Vatomavy, 23.VII.1928, Humbert & Swingle 4810 (P). Reg. Anosy [Prov. Toliara]: Mandrare, vallée de la Manambolo, XII.1953, Bosser 5238 (P); massif du Beampingaratra, vallée de la Maloto, 31.X.1928, Humbert 6313 (P); Andohahela NP, Manongotry, 28 km before Ranomafana, 1.XI.2011, Vorontsova et al. 697 (K, TAN). Reg. DIANA [Prov. Antsiranana]: montagne d'Ambre, VII.1953, Bosser 5338 (K, P). Reg. Ihorombe [Prov. Fianarantsoa]: Andringitra PN, forêt de Ravaro, 9.I.2000, Messmer et al. 834 (P). Reg. Itasy [Prov. Antananarivo]: massif de l'Ankaratra, flanc oriental du Tsiafajavona, 15.VII.1928, Decary et al. 4570 (K, P). Reg. SAVA [Prov. Antsiranana]: pentes occidentales du massif de Marojejy, à l'E de Ambalamanasy II, 30.XI.1948, Humbert & Capuron 22281 (P). Reg. Sofia [Prov. Mahajanga]: montagnes au N de Mangindrano jusqu'aux sommets de Ambohimirahavavy, 19.I.1951, Humbert & Capuron 25249 (P). Reg. Vakinankaratra [Prov. Antananarivo]: Manjakatompo, III.1961, Bosser 15116 (K, P). Reg. Vatovavy [Prov. Fianarantsoa]: Ranomafana PN, bords de la Namorona, I.1964, Bosser 18926 (P).

  • Fig. 7.

    Brachiaria subrostrata A. Camus. A. Habit; B. Ligule; C. Leaf; D. Spikelet; E. Lower glume, dorsal view; F. Upper glume, dorsal view; G. Lower lemma, dorsal view; H. Upper floret, dorsal view; I. Upper lemma, dorsal view; J. Caryopsis. [Drawing: Roger Lala Andriamiarisoa]

    img-z16-1_199.jpg

    Fig. 8.

    A, B. Brachiaria subrostrata A. Camus; C. Brachiaria tsiafajavonensis A. Camus; D–F. Brachiaria umbellata (Trin.) Clayton. [A: Vorontsova et al. 2397; B: Rokiman et al. 2045; C: Vorontsova et al. 697; D: Vorontsova et al. 1900; E: Mandena 2.XI.2011; F: Hall et al. 17] [Photos: Maria S. Vorontsova]

    img-z17-1_199.jpg

    Fig. 9.

    Distribution maps. Brachiaria subrostrata A. Camus (stars), B. tsiafajavonensis A. Camus (triangles), B. umbellata (Trin.) Clayton (circles), and Echinochloa hubbardii (A. Camus) Voronts. (squares).

    img-z18-1_199.jpg

    11. Brachiaria umbellata (Trin.) Clayton in Kew Bull. 34: 559.

  • 1980 (Fig. 8D–F, 11A).

  • Panicum umbellatum Trin., Gram. Panic.: 238. 1826.

  • Holotypus: Mauritius: sine loco, 1825, Sieber Hb. Maur. II. No. 34 (LE Herbarium Trinii 996.1 microfiche!; iso-: BR [BR0000008756435] image!, G [G00022428, G00022429] image!, H [H1048911, H1568372] image!, K [K000244716]!, L [L0043864, L0043865, L0043866] image!, MO [MO-1742146] image!, P [P00450345, P00450346]!, US [US-2903023 fragm., US-144576]!, W [W0000261, W0000262, W0000263, W0000264, W18890211252, W18890236430, W18890236431, W18890236432, W18890236433] image!).

  • = Panicum nossibense Steud., Syn. Pl. Glumac. 1(6): 419. 1854. = Panicum umbellatum subsp. nossibense (Steud.) A. Camus in Notul. Syst. (Paris) 15: 414. 1959. Lectotypus (designated here): Madagascar. Reg DIANA [Prov. Antsiranana]: Nosy Be, VI.1847, Boivin 1962 or s.n. (P [P00450237]!; isolecto-: K [K000805712]!, P [P00450238, P00450239]!, US [US-1389878 fragm.]!, W [W0023752] image!).

  • Stoloniferous mat-forming perennial, prostrate with ascending flowering culms, to 30 cm high, culms much branched, rooting at nodes, glabrous or finely pilose. Leaf sheath glabrous to pubescent. Ligule a line of hairs. Leaf blade narrow-lanceolate, thickly chartaceous, 1–3(–4) × 0.2–0.6 cm, glabrous to pubescent on both sides. Inflorescence racemose, slender, open or contracted, 1.5–5.5 cm long. Racemes 4–8, 1.5–5.5 cm long, erect, decreasing in length upwards, on a common axis 0–2 cm long, sometimes with secondary branches, rhachis narrow, with trichomes 1–2 mm long, spikelets not overlapping with adjacent spikelets, single, on pedicels of uneven length, bare at base. Spikelets elliptic, apically acute, 1.5–2 mm long, drying whiteish, often with a purple tinge. Lower glume absent or ⅛–⅓ as long as spikelet, membranous, obtuse to emarginate, with no veins, glabrous, orientation relative to rhachis variable. Upper glume as long as spikelet or a little shorter, membranous, 3–5-veined, glabrous or sometimes finely pilose. Lower floret infertile, palea absent. Lower lemma membranous, 5-veined, glabrous or sometimes finely pilose. Upper lemma acute, shiny to rugulose.

  • Distribution and ecology. – Madagascar, Comores, Seychelles, Mauritius, Rodrigues. Its status as an island group endemic is not clear: scattered records from Malawi, Mozambique, Tanzania, and Zimbabwe are most likely repeated introductions (Fig. 9).

  • Forms the dominant ground cover across significant areas of Madagascar and surrounding islands except the arid southwest. Abundant especially in sandy coastal areas but also on highland grazing lawns not affected by fire, and mid-elevation forest clearings, at elevations 0–1600 m. Common lawn grass. Apparently unable to tolerate the aridity of the southwest.

  • Notes. – Abundant and ecologically significant species. Introduced as a lawn grass to several localities in southern Africa (Clayton & Renvoize, 1982), and known as “coconut lawn”, “gazon cocotier” in Mayotte [P00290436]. Considerable variability across the range becomes visible when examined under a binocular microscope: occasionally the lower glume is absent altogether, fine trichomes can appear on the spikelet, and the upper lemma can be either shiny or finely rugulose.

  • Boivin's Nosy Be collections of Brachiaria umbellata are numerous and it is not possible to verify which ones may have originally constituted a single gathering, or which exact sheet Steudel (1854) may have been referring to as “Boivin legit in Ins. Nossibé”, not citing a collection number. The more comprehensive and fully labelled sheets of these collections bear the number 1962 and a collection date of June 1847, while others only bear the printed date range 1847–1852. The lectotype selected here is the best quality and most extensively annotated sheet of Boivin's herbarium.

  • Selected specimens examined. – Madagascar. Reg. Amoron'i Mania [Prov. Fianarantsoa]: Ambatofinandrahana, Itremo, pepinière de la NAP à Ihazofotsy, 21.II.2014, Nanjarisoa et al. 164 (K, TAN). Reg. Analamanga [Prov. Antananarivo]: Manjakandriana, 4.IV.1951, Bosser 647 (P); Antananarivo, Tsimbazaza, IV.1961, Bosser 15353 (P, TAN); Beronono, c. 4 km from Ankazobe to Ankafobe, 8.V.2017, Solofondranohatra & Razanatsoa 1020 (K, P, TAN). Reg. Analanjirofo [Prov. Toamasina]: Soanierana Ivongo, Manankinany, 25.X.1986, Pettersson & Nilsson 38 (P). Reg. Anosy [Prov. Toliara]: Vinanibe près du Fort-Dauphin, 14.VIII.1932, Decary 10292 (P); Taolagnaro, Mandromodromotra, I.1959, Peltier & Peltier 1497 (P, TAN); Sainte-Luce, Ambandrika, 29.II.2012, Ramananjanahary et al. 558 (P). Reg. Atsinanana [Prov. Toamasina]: Ilaka-Est, XII.1962, Bosser 16882 (K, P, TAN); Tamatave, III.1932, Jard. Bot. Tananarive 324186 (P, TAN). Reg. Boeny [Prov. Mahajanga]: Ankarafantsika NP office, 14.II.2017, Vorontsova & Duncan-Rice 2092 (K, P, TAN). Reg. DIANA [Prov. Antsiranana]: Nosy-Be, Ambatoloaka, VIII.1959, Bosser 13230 (P, TAN); Sahafary Forêt, VI.1970, Bosser 20382[b] (K); Manongarivo, Besinkara, Ambalafary, 13.V.1995, Gautier & Chatelain 2644 (G, K, P, TAN). Reg. Ihorombe [Prov. Fianarantsoa]: près de Ranotsara, XII.1963, Bosser 18728 (P, TAN). Reg. Melaky [Prov. Mahajanga]: marais d'Antsalova, X.1963, Morat 163 (TAN). Reg. Sofia [Prov. Mahajanga]: sur le Mahajamba à Beronono, I.1907, Perrier de la Bâthie 11144[a] (P). Reg. Vatovavy [Prov. Fianarantsoa]: env. d'Ambila, 18.III.1951, Benoist 829 (P, TAN).

  • Fig. 10.

    Brachiaria tsiafajavonensis A. Camus. A. Habit; B. Ligule; C. Panicle branch; D. Spikelet; E. Lower glume, ventral view; F. Lower glume, dorsal view; G. Upper glume, ventral view; H. Upper glume, dorsal view; I. Lower lemma, ventral view; J. Lower lemma, dorsal view; K. Lower palea; L. Upper floret, ventral view; M. Upper lemma, ventral view; N. Upper lemma, dorsal view; O. Upper palea, ventral view; P. Upper palea, dorsal view; Q. Upper floret lodicules. Scale bar: A = 2.5 cm; B = 3.3 mm; C = 2 mm; D–Q = 1.5 mm. [Bosser 15116, K] [Drawing: Lucy T. Smith]

    img-z19-1_199.jpg

    12. Echinochloa hubbardii (A. Camus) Voronts., comb. nov. (Fig. 11B–C).

  • Brachiaria hubbardii A. Camus in Bull. Soc. Bot. France 94: 40. 1947. ≡ Acroceras hubbardii (A. Camus) Clayton in Kew Bull. 34: 557. 1980. ≡ Panicum hubbardii (A. Camus) Renvoize in Hautrey et al., Fl. Mascareignes 203: 123. 2018.

  • Lectotypus (designated here): Madagascar. Reg. DIANA [Prov. Antsiranana]: Nosy Be, V.1879, Hildebrandt 2985 (P [P02233603]!; isolecto-: GOET [GOET005565] image!, K [K000244701, K000244702]!, P [P02233606, P02233612]!, US!). Syntypi: Comoros. Anjouan: Tsantsany, XII.1921, Decary 810 (P [P00216311]!); ibid. loco, VIII.1923, Waterlot 918 (P [P00216314]!). Grande Comore: Vouni, V.1850, Boivin s.n. (P [P00216307]!). Madagascar. Reg. Analanjirofo [Prov. Toamasina]: Sainte Marie, V.1852, Boivin s.n. (P [P02233596]!). Mayotte: Majimbini forest, V.1884, Humblot 1092 (P [P00216308, P00216309, P00216310]!); ibid. loco, s.d., Boivin s.n. (K [K000805482]!).

  • Tanzania. Zanzibar: XI.1873, Hildebrandt 1100 (GOET [GOET005564] image!, P [P00442051]!).

  • = Brachiaria hubbardii var. halophila A. Camus in Bull. Soc. Bot. France 101: 395. 1954. Holotypus: Madagascar. Reg. Boeny [Prov. Mahajanga]: Anjiajia, VIII.1952, Bosser 3500 (P [P02233608]!; iso-: K [K000244703]!).

  • = Brachiaria nodosa Renvoize & Bosser in Hautrey et al., Fl. Mascareignes 203: 139. 2018, syn. nov. Holotypus: Mauritius: Serpent Island, XII.1971, Vinson s.n. (MAU [MAU15188] image!).

  • Stoloniferous mat-forming perennial, prostrate with ascending flowering culms, to 20 cm high, culms much branched, rooting at nodes, glabrous, nodes bearded. Leaf sheath glabrous to pubescent. Ligule absent. Leaf blade linear, membranous, 1–4 × 0.1–0.2 cm, glabrous to pubescent on both sides. Inflorescence capitate, 0.5–1.5 cm long, with 5–15(–30) spikelets. Racemes 1–4, 0–0.3 cm long, barely separable within capitate inflorescence, on a common axis 0–1 cm long, with no secondary branching, rhachis narrow, glabrous, spikelets overlapping with adjacent spikelets, single, subsessile. Spikelets elliptic, apically acute, 2–2.3 mm long, white to pale green. Lower glume ½–⅔ as long as spikelet, membranous, acute, 3–5-veined, glabrous or sometimes apically pubescent, orientation relative to rhachis variable. Upper glume as long as spikelet or a little shorter, membranous, pinched at apex, 5–7-veined, glabrous or sometimes apically pubescent. Lower floret male, palea as long as lemma, anthers 3, c. 1.2 mm long. Lower lemma membranous, pinched at apex, 5–7-veined, glabrous or sometimes apically pubescent. Upper lemma acute, smooth, shiny, white becoming pale brown, with an apical green crest.

  • Distribution and ecology. – Sea shores, associated with puddles and temporary water bodies. Readily forms short dense grazing lawns and turf. Frequently associated with human activity and commonly seen on pavements, between paving slabs, and within local pastures and sports turf. Not recorded in Tanzania since Hildebrandt 1100, the single syntype collection made in 1873 (Fig. 9).

  • Notes. – Echinochloa hubbardii (A. Camus) Voronts. is recognised by its long-exserted capitate inflorescences, short soft leaf blades, and diminutive mat-forming habit. The complete absence of a ligule is consistent with the Hackel et al. (2018) phylogenetic placement of this species in Echinochloa, a genus commonly lacking a ligule.

  • Echinochloa hubbardii is sympatric with the closely related miniature trailing Mascarene species E. serpens (Kunth) Voronts. (comb. nov., see below), which is also occasionally present in Madagascar and has similar globose inflorescences and lacks of ligule but sessile inflorescences with fewer spikelets, and with glumes and lower lemma which are always pilose. From the overall appearance of the plants it is quite clear that E. hubbardii and E. serpens are closely related, and different from all the other species in Acroceras, Brachiaria, Echinochloa, Panicum s.l., and Urochloa. This relationship between Echinochloa hubbardii and E. serpens was previously obscured by the traditional generic concepts and thus confusingly variable generic placements of these species in Brachiaria [B. hubbardii A. Camus in Bosser, 1969], Acroceras [A. hubbardii (A. Camus) Clayton in Clayton & Renvoize, 1982], and Panicum as well as Brachiaria [Panicum hubbardii (A. Camus) Renvoize, Brachiaria serpens (Kunth) C.E. Hubb., and B. nodosa Renvoize & Bosser in Bosser & Renvoize, 2018].

  • Brachiaria nodosa is morphologically consistent with Echinochloa hubbardii but with more indumentum on the distal parts of its spikelets than average, thus similar to E. serpens but with exserted inflorescences and longer spikelets. The type of Brachiaria hubbardii var. halophila A. Camus displays densely hirsute leaf sheaths and leaf blades and thus a paler specimen colour, but no other differences are observed.

  • Many of the older specimens of both Echinochloa hubbardii and E. serpens are annotated as “Panicum conglomeratum L.” and a specimen of E. hubbardii is present in the Linnaean herbarium: Herb. Linn. 80.29http://linnean-online.org/1261]. Due to confusion with the sympatric and superficially similar Sacciolepis indica (L.) Chase, the name Panicum conglomeratum L. is illegitimate and referrable to Sacciolepis indica (Hubbard & Vaughan, 1940; Cafferty et al., 2000; Jarvis, 2007). The lectotype of Brachiaria hubbardii is designated here for its superior quality material and also to maintain continuity with Bosser & Renvoize (2018) who cited Hildebrandt 2985 at P as the holotype.

  • Selected specimens examined. – Madagascar. Reg. Betsiboka [Prov. Mahajanga]: massif causses du Kelifely, XI.1974, Morat 4671 (P). Reg. Boeny [Prov. Mahajanga]: Anjiajia, VIII.1952, Bosser 3500 (K, P); Madirovalo, VI.1901, Perrier de la Bâthie 168[a] (K). Reg. DIANA [Prov. Antsiranana]: vallée de l'Ifasy en aval d'Anaborano, 31.III.1951, Humbert & Capuron 25864 (P); Nosy Be, dans la rue de Helville, VIII.1933, Perrier de la Bâthie s.n. (P, TAN); Ambilobe, roadside opposite Jovenna petrol station, 11.X.2011, Vorontsova et al. 347 (K, TAN). Reg. Menabe [Prov. Toliara]: environs de Morondava, IX.1956, Bosser 9918 (P).

  • Fig. 11.

    A. Brachiaria umbellata (Trin.) Clayton; B, C. Echinochloa hubbardii (A. Camus) Voronts.; D–F. Urochloa brizantha (Hochst. ex A. Rich.) R.D. Webster. [A: Tzimbazaza 24.II.2022; B: Vorontsova et al. 2115; C: Vorontsova et al. 2124; D: Vorontsova et al. 2396; E: Vorontsova et al. 2398; F: Randriatsara et al. 3] [Photos: Maria S. Vorontsova]

    img-z21-1_199.jpg

    13. Echinochloa leandriana (Bosser) Voronts., comb. nov.

  • Brachiaria leandriana Bosser in Adansonia, sér. 2, 6: 111. 1966.

  • Holotypus: Madagascar. Reg. Atsimo-Andrefana [Prov. Toliara]: plateau Mahafaly, W de Ejeda, III.1960, Bosser 14538 (P [P00450182]!; iso-: [P00450183, P00450184]!, TAN!).

  • Loosely tufted mat-forming stoloniferous perennial, ascending to erect, to 30 cm high, culms thickened and knotty at base, glabrous, nodes bearded. Leaf sheath pubescent, silky at base. Ligule absent. Leaf blade narrow-lanceolate, chartaceous, 4–8 × 0.3–0.7 cm, pubescent on both sides. Inflorescence racemose, thick, contracted or subcapitate, 3–6 cm long. Racemes 4–7, 0.6–2.5 cm long, decreasing in length upwards, on a common axis 1–4 cm long, with no secondary branching, rhachis triquetrous, finely pubescent, spikelets overlapping untidily with adjacent spikelets, paired, subsessile, in 4 untidy rows. Spikelets ovate, apically apiculate, 2–2.2 mm long, whiteish. Lower glume ⅔–¾ as long as spikelet, herbaceous, apiculate, 3–5-veined, hirsute, orientation relative to rhachis variable. Upper glume as long as spikelet, herbaceous, apiculate, 7–9-veined, veins pronounced, hirsute. Lower floret male, palea as long as lemma. Lower lemma herbaceous, 5–7-veined, hirsute. Upper lemma apiculate, smooth, shiny, pale.

  • Distribution and ecology. – Endemic to the Mahafaly plateau in arid inland southwestern Madagascar, forming spreading mats in open canopy secondary vegetation on limestone (Fig. 12).

  • Notes. – This species is known from only three collections by Jean Bosser and has not been seen since 1963. It is not clear why Bosser (1966) described this material in the genus Brachiaria given its striking resemblance to Echinochloa, including the lack of ligule characteristic of Echinochloa illustrated in Bosser (1966). Compared to Brachiaria and Urochloa s.l., this is a distinctive species with dense whiteish inflorescences and bearded nodes. Unpublished DNA sequences place it firmly in Echinochloa in the subtribe Boivinellinae (Bosser 16110, P02233533, G. Besnard & J. Hackel, pers. comm.). A full revisison of Echinochloa in Madagascar is beyond the scope of this work; the species is here transferred to Echinochloa pending a more detailed assessment of species boundaries.

  • Additional specimens examined. – Madagascar. Reg. Atsimo-Andrefana [Prov. Toliara]: Ankalirano (Ankadirano), plateau Mahafaly, III.1962, Bosser & Viennot 16110 (P); Betioky, Ekinaty, III.1963, Bosser 19687 (P).

  • 14. Echinochloa serpens (Kunth) Voronts., comb. nov.

  • Panicum serpens Kunth, Rev. Gram. 1: 38. 1829 [nom. nov.]. ≡ Panicum parvifolium var. serpens (Kunth) Baker, Fl. Mauritius: 438. 1877. ≡ Brachiaria serpens (Kunth) C.E. Hubb. in Kew Bull. 1939: 654. 1939.

  • Panicum repens Nees, Fl. Bras. Enum. Pl. 2(1): 171. 1829 [nom. illeg., non P. repens L., 1762].

  • Holotypus: Mauritius: sine loco, Bory de St Vincent. No. 40 (B-W [BW18793010] image!).

  • = Brachiaria lateritica A. Camus in Bull. Soc. Bot. France 93: 89. 1946, syn. nov. Holotypus: Madagascar. Reg. DIANA [Prov. Antsiranana]: env. de Diégo-Suarez, VIII.1933, Perrier de la Bâthie 19296 (P [P02233536]!).

  • Stoloniferous mat-forming perennial, forming dense cushions, not rising more than c. 2 cm above ground, culms much branched, rooting at nodes, glabrous, nodes bearded. Leaf sheath pubescent. Ligule absent. Leaf blade narrow-lanceolate, membranous, 0.7–1.5(–1.8) × 0.08–0.12(–0.15) cm, sparsely to densely pubescent on both sides. Inflorescence capitate, not fully exserted, 0.3–0.5(–0.8) cm long, with 3–5(–8) spikelets, with no secondary branching, rhachis narrow, glabrous to pubescent, spikelets overlapping with adjacent spikelets, single, subsessile. Spikelets elliptic, apically acute, 1–1.5(–2) mm long, white to pale green. Lower glume ½–⅔ as long as spikelet, membranous, acute, 3-veined, glabrous to apically pubescent, orientation relative to rhachis variable. Upper glume as long as spikelet or slightly shorter, membranous, pinched at apex, 5–7-veined, pubescent, often with bulbous-based hairs. Lower floret male, palea as long as lemma. Lower lemma membranous, pinched at apex, 5–7-veined, pubescent, often with bulbous-based hairs. Upper lemma acute, smooth, shiny, white becoming pale brown, with an apical green crest.

  • Distribution and ecology. – The only collection known from Madagascar is the type of Brachiaria lateritica A. Camus (Fig. 12).

  • Notes. – Details of the species boundary between Echinochloa hubbardii and E. serpens are not altogether clear and require field work. These species seem to be sympatric, forming ground cover at low elevations on the islands. Herbarium specimens of E. serpens consistently differ from E. hubbardii by their more compact habit, uniform short leaf blades and short peduncles, and pubescence on leaf blades and spikelets. These two species are maintained here as separate taxa in agreement with Hubbard and the Kew collections as documented by Camus (1947), and also in agreement with Bosser & Renvoize (2018). For discussion of the relationship between E. hubbardii and E. serpens and their generic placement see the notes under E. hubbardii.

  • This species has historically been refereed to as “Panicum conglomeratum”; see notes under Echinochloa hubbardii. The protologue of Panicum repens Nees (Nees von Esenbeck, 1829) cites “in insula Mauritii (Sieb. Herb. n. 34)” and this number is also cited by Baker (1877) in his description of Panicum parvifolium var. serpens (Kunth) Baker. Unfortunately, Baker conflates this species with the superficially similar P. umbellatum Trin. (= Brachiaria umbellata in this treatment). The collection Sieber Hb. Maur. II. No. 34 is the type of Panicum umbellatum, and all the sheets examined clearly belong to Brachiaria umbellata, not Echinochloa serpens.

  • Fig. 12.

    Distribution maps. Echinochloa leandriana (Bosser) Voronts. (stars), E. serpens (Kunth) Voronts. (triangles), Moorochloa eruciformis (Sm.) Veldkamp (circles), and Urochloa arrecta (Hack. ex T. Durand & Schinz) Morrone & Zuloaga (squares).

    img-z23-10_199.jpg

    15. Moorochloa eruciformis (Sm.) Veldkamp in Reinwardtia 12: 139. 2004.

  • Panicum eruciforme Sm. in Sibthorp, Fl. Graec. Prodr.: 40. 1806. ≡ Brachiaria eruciformis (Sm.) Griseb., Fl. Ross. (Ledeb.) 4: 469. 1853. ≡ Urochloa eruciformis (Sm.) C. Nelson & Fern. Casas in Fontqueria 51: 4 .1998.

  • Holotypus: Greece: sine loco, s.d., Sibthorp s.n. (OXF).

  • Loosely tufted annual, ascending to erect, 0.1–0.6 m high, culms not branched, glabrous, nodes bearded. Leaf sheath glabrous to sparsely pubescent. Ligule a line of hairs. Leaf blade linear, chartaceous, 2–15 × 0.2–0.6 cm, glabrous to pubescent on both sides, retrorse at maturity. Inflorescence racemose, slender, contracted, 2–10 cm long. Racemes 3–14, 0.5–2.5 cm long, roughly even in length, appressed, on a common axis 1–8 cm long, with no secondary branching, rhachis triquetrous, pubescent, spikelets imbricate, single, subsessile, in 2 tidy rows. Spikelets elliptic, apically acute, 1.7–2.7 mm long, whiteish. Lower glume up to 1/5 as long as spikelet, membranous, truncate to acute, 1-veined, glabrous to pubescent, turned towards rhachis. Upper glume as long as spikelet, membranous, 5-veined, pubescent (rarely glabrous). Lower floret infertile or male, palea c. ⅔ to as long as lemma, anthers 3, 0.5–1 mm long. Lower lemma membranous, 5-veined, pubescent (rarely glabrous). Upper lemma obtuse, smooth, shiny, yellow to pale brown.

  • Distribution and ecology. – It seems relatively uncommon in Madagascar and restricted to the arid south (Fig. 12).

  • Notes. – Arrangement of spikelets on the racemes appears remarkably tidy and compact, rendering this species easy to recognise. Occurs over much of Africa and Asia, naturalised in Australia and Latin America, but a comparatively small number of collections are known from Madagascar. For the history of the generic name see Veldkamp (2004).

  • Additional specimens examined. – Madagascar. Reg. Atsimo-Andrefana [Prov. Toliara]: env. de Tulear, XI.1956, Bosser 10549 (P); Andranovory, 19.X.1960, Peltier & Peltier 2517 (P).

  • 16. Urochloa arrecta (Hack. ex T. Durand & Schinz) Morrone & Zuloaga in Darwiniana 31: 69. 1992.

  • Panicum arrectum Hack. ex T. Durand & Schinz, Consp. Fl. Afr. 5: 741. 1894. ≡ Brachiaria arrecta (Hack. ex T. Durand & Schinz) Stent in Bothalia 1: 26. 1924.

  • Lectotypus (designated by Sosef 2016: 358): South Africa. Eastern Cape: Komgha Division, near Kei River, s.d., Drège s.n. (K [K000282184]!).

  • = Brachiaria arrecta var. madecassa A. Camus in Bull. Soc. Bot. France 101: 395. 1954. Holotypus: Madagascar. Reg. Vakinankaratra [Prov. Antananarivo]: near Antsirabe, I.1914, Perrier de la Bâthie 10756 (P [P00450159]!; iso-: P [P02040480]!).

  • Loosely tufted stoloniferous perennial, ascending to erect, 0.5–1.3 m high, culms sparsely branched, rooting at lower nodes, glabrous. Leaf sheath glabrous, sometimes pubescent at base of plant. Ligule a line of hairs. Leaf blade linear to narrow-lanceolate, thickly chartaceous, 4–20 × 0.3–1.2 cm, glabrous on both sides. Inflorescence racemose, slender, open, 5–30 cm long. Racemes 2–5, 2–10 cm long, roughly even in length, on a common axis 5–25 cm long, with no secondary branching, rhachis narrowly winged, 0.5–1.5 mm wide, margins scabrid or with cilia up to 0.5 mm long, spikelets imbricate, single, subsessile, in 2 rows, pedicels often pubescent. Spikelets elliptic, apiculate, 3.5–4 mm long, yellowish, often with a purple tinge. Lower glume c. ½ as long as spikelet, membranous, obtuse, 3-veined, glabrous, turned towards rhachis. Upper glume as long as spikelet, membranous, 5–7-veined, glabrous. Lower floret male, palea as long as lemma, anthers 3, c. 2.2 mm long. Lower lemma membranous, 5–7-veined, glabrous. Upper lemma obtuse, rugulose.

  • Distribution and ecology. – Common element of pastures, grazing lawns, open savannas, stream banks, roadsides, rice paddies, and swamps in central and eastern Madagascar, at elevations of 1000–1700 m (Fig. 12).

  • Notes. – Common native African forage grass. Much larger plant than Urochloa distachyos (L.) T.Q. Nguyen or U. nana (Stapf) Voronts. (comb. nov., see below); its mainly erect habit is a useful recognition feature. Distinguished from U. brizantha, U. eminii, and U. jubata (Fig. & De Not.) Sosef by the absence of long cilia on the edges of its rhachis, with cilia only up to 0.5 mm long (1.5–3 mm long in U. brizantha). The lower part of the plant is often underwater. Provides good quality forage in the dry season (Bosser, 1969).

  • Selected specimens examined. – Madagascar. Reg. Alaotra-Mangoro [Prov. Toamasina]: Morarano, W du Lac Alaotra, XII.1954, Bosser 7465 (P); Ambatondrazaka, Manakambahiny Est, 24.XII.1962, Rakotovao 12358 (P). Reg. Amoron'i Mania [Prov. Fianarantsoa]: Ambositra, riviere de Fatihita, 25.I.2015, Manjato et al. 620 (MO, P); 2 km E of Anjomanakona towards Ivato, 27.II.2013, Vorontsova et al. 1036 (K, TAN). Reg. Analamanga [Prov. Antananarivo]: Ilafy, VI.1905, Alleizette 162a (P); Antananarivo-Sud, Ampitatafika, PK 10 rte. d'Arivonimamo, II.1961, Bosser 15154 (P, TAN). Reg. Atsinanana [Prov. Toamasina]: Ilaka-Est, station d'essai “Caroline”, XII.1962, Bosser 16827 (P). Reg. DIANA [Prov. Antsiranana]: rte. d'Ambilobe à Ambanja, XII.1964, Morat 1208 (P). Reg. Sofia [Prov. Mahajanga]: Bealanana, Betainkankana, Ankaizina, V.1952, Bosser 2748 (P). Reg. Vakinankaratra [Prov. Antananarivo]: Ambohimandroso, Analamahitsy village, 26.IV.2017, Solofondranohatra et al. 883 (K, P, TAN). Reg. Vatovavy [Prov. Fianarantsoa]: Vohitranivo, XI.1952, Bosser 3976 (P).

  • 17. Urochloa brizantha (Hochst. ex A. Rich.) R.D. Webster, Austral. Paniceae (Poaceae) 233. 1987 (Fig. 11D–F).

  • Panicum brizanthum Hochst. ex A. Rich., Tent. Fl. Abyss. 2: 363. 1850. ≡ Brachiaria brizantha (Hochst. ex A. Rich.) Stapf in Oliv., Fl. Trop. Afr. 9: 531. 1919.

  • Lectotypus (designated by Veldkamp, 1996: 417): Ethiopia. Tigray: Mt. Scholoda (Selleuda), X.1837, Schimper 89 (P [P00442084]!; isolecto-: BM [BM000923191]!, BR [BR0000008645142, BR0000008366955] images!, G [G00015881, G00015882, G00015883, G00015884] images!, GOET [GOET006080] image!, K [K000282126, K000282127, K000282128]!, L [L0043836, L0043837] images!, LG [LG0000090036057, LG0000090036200] images!, M [M0103976, M0103977] images!, MO [MO-1742002] image!, MPU [MPU024477, MPU024478] images!, P [P00442082, P00442083, P00731455, P02284802, P02284803]!, PRE [PRE0664145-0] image!).

  • Tufted perennial, firmly rooted and almost woody near base of mature stand, ascending to erect, 0.3–2 m high, culms not branched, glabrous to sparsely hirsute. Leaf sheath glabrous to sparsely pilose. Ligule a ciliate membrane. Leaf blade broadly linear, chartaceous, 10–100 × 0.3–2 cm, glabrous to sparsely pilose on both sides. Inflorescence racemose, stout, erect, 5–25 cm long. Racemes 2–16, 4–20 cm long, usually gently curved, on a common axis 3–20 cm long, with no secondary branching, rhachis herbaceous, curved, 1–1.5 mm wide, margin ciliate with trichomes 1.5–3 mm long, spikelets imbricate, single, subsessile, in a single row. Spikelets plump elliptic to obovate, apically subacute, 4–6 mm long, white-yellowish, often with a purple tinge. Lower glume c. ⅓ as long as spikelet, membranous, clasping, acute or obtuse, 5-veined, glabrous, separated from rest of spikelet by a short internode, turned towards rhachis. Upper glume almost as long as spikelet, cartilaginous, dully shining, 5–7-veined, glabrous or pubescent. Lower floret male, palea as long as lemma. Lower lemma somewhat concave, cartilaginous, dully shining, 5–7-veined, glabrous or pubescent. Upper lemma acute, smooth to rugulose.

  • Distribution and ecology. – Recorded occurrences appear to reflect past forage plantings along roadsides, as well as agricultural stations. Open roadside grazing lawns, at elevations of 800–1600 m (Fig. 13).

  • Notes. – African forage species bred as a forage crop, introduced to Madagascar in the twentieth century, and now grown as a successful forage crop in the highlands (Bosser, 1969). Agricultural literature in Madagascar frequently refers to “brachiaria”, which appears to indicate this species rather than any of the others.

  • In spite of the comparatively low number of herbarium records, Urochloa brizantha is commonly seen naturalised on the roadsides, for example in Ankafobe and near Moramanga. Usually seen forming a dense monotypic sward of firmly-rooted erect plants with woody culm bases (Fig. 11D–F). Diagnostic characters of U. brizantha include shiny cartilaginous upper glume and lower lemma (herbaceous in U. eminii, including the previously distinct species Brachiaria ruziziensis R. Germ. & C.M. Evrard), narrow rhachis (wide in U. eminii), and tufted habit (stoloniferous in U. eminii), although all of these intergrade into U. eminii.

  • Additional specimens examined. – Madagascar. Reg. Alaotra-Mangoro [Prov. Toamasina]: Alaotra Agricultural Station, IX.1953, Bosser 7103 (TAN); Alaotra, XII.1963, Morat 251 (TAN); Moramanga, road from Andasibe to Vakona, turnoff towards Ambatovy mine, 22.II.2019, Vorontsova et al. 2396 (K, TAN). Reg. Analamanga [Prov. Antananarivo]: Manjakandriana, Sohisika Association office at entrance to Ankafobe PA, 1.III.2019, Vorontsova et al. 2398 (K, TAN). Reg. Bongolava [Prov. Antananarivo]: Kianjasoa, 15.IV.1962, Boudet 1157 (P [P02520029]).

  • Fig. 13.

    Distribution maps. Urochloa brizantha (Hochst. ex A. Rich.) R.D. Webster (stars), U. deflexa (Schumach.) H. Scholz (triangles), U. distachyos (L.) T.Q. Nguyen (circles), and U. eminii (Mez) Davidse (squares).

    img-z26-1_199.jpg

    18. Urochloa deflexa (Schumach.) H. Scholz in Bull. Mus. Natl. Hist. Nat., B, Adansonia 11: 443. 1989 (Fig. 14A, B).

  • Panicum deflexum Schumach., Beskr. Guin. Pl.: 63. 1827.≡ Panicum ramosum var. deflexum (Schumach.) Peter in Repert. Spec. Nov. Regni Veg. Beih. 40: 177. 1930. ≡ Brachiaria deflexa (Schumach.) C.E. Hubb. ex Robyns in Bull. Jard. Bot. État Bruxelles 9: 181. 1932.

  • Holotypus: Ghana: southern part of the country, s.d., Thonning 390 (C [C10004257] image!; iso-: C [C10004258, C10004259] image!, K [K000282165]!).

  • Loosely tufted annual, largely erect, to 0.7 m high, culms weakly branched, glabrous. Leaf sheath glabrous to sparsely pubescent towards top. Ligule a line of hairs. Leaf blade lanceolate, chartaceous, 8–17 × 0.4–1.2 cm, glabrous to sparsely pubescent on both sides. Inflorescence racemose, effuse, open, 5–15 cm long. Racemes 6–15, 2–8 cm long, flexuous, decreasing in length upwards, on a common axis 3–12 cm long, sometimes with small secondary branches, rhachis triquetrous, ciliate, spikelets not overlapping with adjacent spikelets, paired, sessile and shortly pedicelled in each pair, at least some pedicels longer than spikelets. Spikelets broadly elliptic, plump, apically apiculate, 3–3.3 mm long, whiteish. Lower glume c. ½ as long as spikelet, membranous, clasping, acute, 3–5-veined, glabrous to hirsute, separated from rest of spikelet by an internode c. 0.5 mm long, orientation relative to rhachis variable. Upper glume as long as spikelet, herbaceous, apiculate, 7-veined, veins pronounced, hirsute. Lower floret infertile, palea ⅔–¾ as long as lemma. Lower lemma herbaceous, 5-veined, cross veins sometimes visible, hirsute. Upper lemma acute, rugose.

  • Distribution and ecology. – Likely native, adventitious African and south Asian grass common in drier western and especially southern parts of Madagascar. Roadsides, dry forest and spiny forest understory, savanna, cultivation, on sand, laterite, and a variety of substrates, at elevations of 0–1300m (Fig. 13).

  • Notes. – A key character for Urochloa deflexa (Schumach.) H. Scholz is the presence of at least some pedicels which are longer than the spikelet (Fig. 14A, B). On smaller individuals the inflorescence is often larger than the rest of the plant. Clayton & Renvoize (1982) noted continuous variation between U. deflexa and U. ramosa (L.) T.Q. Nguyen but these seem to be distinct in Madagascar. The inflorescences of U. deflexa can appear to be paniculate rather than racemose, and it is therefore regularly mistaken for Panicum.

  • Urochloa deflexa is a weed of a broad range of arid lower elevation localities. It forms the ground cover in many disturbed areas, such as the Ankarafantsika National Park visitor centre. Unlike other parts of Africa, there is no evidence of the grain being eaten by people in Madagascar.

  • Selected specimens examined. – Madagascar. Reg. Anosy [Prov. Toliara]: 23–28 km W of Manambaro, 21.II.1975, Croat 31978 (K, MO, TAN); Tolagnaro, Amboasary-Sud, Somangy, 8 km from Amboasary to Berenty, 15.III.2019, Rakotomalala et al. 274 (K, TAN). Reg. Boeny [Prov. Mahajanga]: Ambondromamy, 13.II.2013, Vorontsova et al. 914 (K, TAN). Reg. DIANA [Prov. Antsiranana]: Mailaka, II.1892, Douillot s.n. (P); forêt d'Analamahitso au Sud d'Anivorano-Nord, XII.1937, Humbert 19069 (P); Ambilobe, falaise de l'Ankarana, I.1969, Morat 3087 (P). Reg. Ihorombe [Prov. Fianarantsoa]: bassin de la Malio, près d'Ambalabe, 23.XI.1946, Humbert 19468 (P); près d'Ambalabe, 23.XI.1946, Humbert 20060[b] (K, P, TAN); Ivohibe, haute vallée de la Menarahaka a l'E d'Ihosy, 28.I.1955, Humbert 28615 (P); plateaux et vallées de l'Isalo à l'W de Ranohira, 29.I.1955, Humbert 29845 (P). Reg. Melaky [Prov. Mahajanga]: Mt Bevendro, Tsingy du Bemaraha, 25.XI.1932, Leandri 636 (P); près d'Ambodiriana, entre Antsalova et Tsiandro, Ouest Antsingy forêt, 21.I.1960, Leandri 2672 (P).

  • Fig. 14.

    A, B. Urochloa deflexa (Schumach.) H. Scholz; C, D. Urochloa distachyos (L.) T.Q. Nguyen; E, F. Urochloa reptans (L.) Stapf. [A, B: Ankarafantsika NP 17.II.2018; C: Vorontsova et al. 1774; D: Vorontsova et al. 2117; E, F: Vorontsova et al. 2120] [Photos: Maria S. Vorontsova]

    img-z27-1_199.jpg

    19. Urochloa distachyos (L.) T.Q. Nguyen in Novosti Sist. Vyssh. Rast. 1966: 13. 1966 (Fig. 14C–D).

  • Panicum distachyon L., Mant. Pl.: 183. 1767. ≡ Brachiaria distachyos (L.) Stapf in Oliv., Fl. Trop. Afr. 9: 565. 1919.

  • Lectotypus (designated by Henrard 1950: 191): India: “Habitat in India orientali. Koenig.”, s.d., Herb. Linn. No. 80.41 (LINN-HL80-41 image!).

  • = Panicum subquadriparum Trin., Gram. Panic.: 145. 1826. ≡ Brachiaria subquadripara (Trin.) Hitchc. in Lingnan Sci. J. 7: 214. 1931. ≡ Urochloa subquadripara (Trin.) R.D. Webster, Austral. Paniceae (Poaceae) 252. 1987. Lectotypus (designated by Sosef, 2016: 360): Guam: sine loco, s.d., Chamisso in Herb. Trinius 0974.01 (LE).

  • = Panicum miliiforme J. Presl in C.B. Presl, Reliq. Haenk. 1: 300. 1830. ≡ Brachiaria miliiformis (J. Presl) Chase in Contr. U.S. Natl. Herb. 22: 35. 1920. ≡ Brachiaria subquadripara var. miliiformis (J. Presl) S.L. Chen & Y.X. Jin in Acta Phytotax. Sin. 22: 472. 1984. Holotypus: Philippines. Luzon: sine loco, s.d., Haenke s.n. (PR; iso-: B [B 10 0367348] image!, HAL [HAL0063364] image!, W [W18890237977, W0006077, W0006079] images!).

  • Stoloniferous mat-forming perennial, prostrate with ascending flowering culms, ascending to c. 0.5 m high, culms branched, rooting at lower nodes, often with a knotty rootstock, glabrous. Leaf sheath glabrous or sparsely pubescent with ciliate margins. Ligule a ciliate membrane. Leaf blade linear to narrow-lanceolate, chartaceous, 2–20 × 0.3–1 cm, glabrous to sparsely pubescent on both sides. Inflorescence racemose, slender, open, 3.5–15 cm long, peduncle glabrous to pubescent. Racemes 2–5, 1–6 cm long, gently curved, roughly even in length, on a common axis 0.5–10 cm long, with no secondary branching, rhachis narrowly winged, 0.7–1 mm wide, scaberulous, spikelets imbricate, single, subsessile, in 2 rows. Spikelets plump elliptic to obovate, apically subacute to acute, 2.5–3.7 mm long, whiteish, sometimes tinged with purple. Lower glume ⅓–½ as long as spikelet, membranous, clasping, obtuse, 5–7-veined, glabrous, separated from rest of spikelet by an internode c. 0.5 mm long, turned towards rhachis. Upper glume as long or almost as long as spikelet, membranous, 5–7-veined, glabrous. Lower floret infertile, palea ⅔ as long to almost as long as lemma. Lower lemma membranous, 5-veined, glabrous. Upper lemma subobtuse to acute, rugulose.

  • Distribution and ecology. – Paleotropical forage and adventitious grass common in the warmer lowland parts of Madagascar, and especially common the far north of Madagascar and on Nosy Be. Roadsides, rice paddies and fields of maize and sugarcane, savannas, costal habitats especially on sand, at elevations of 0–600 m (Fig. 13).

  • Notes. – Urochloa distachyos is a known invasive tropical lawn and pasture weed with creeping stolons, typically invading rice paddies and pastures at lower elevations. It seems to be related to U. arrecta (Hackel et al., 2018), which is abundant across the highlands.

  • This treatment follows Sosef (2016) and Morrone & Zuloaga (1992) in treating Urochloa distachyos as conspecific with U. subquadripara (Trin.) R.D. Webster, as part of a possible polyploid complex. Bosser (1969) considered the northern populations previously assigned to Brachiaria subquadripara (Trin.) Hitchc. [B. miliiformis (J. Presl) Chase in Bosser (1969)] with longer spikelets to be recent introductions, making no statement on the origin of the B. distachyos with shorter spikelets in southern and western Madagascar.

  • Selected specimens examined. – Madagascar. Reg. Androy [Prov. Toliara]: Ambovombe Sud, I.1956, Descoings 1577 (P); Andasaria, 20 km before Tsihombe village on the RN 13, 18.III.2019, Rakotomalala et al. 307 (K, TAN). Reg. Atsinanana [Prov. Toamasina]: Tamatave, 13.VII.1964, Tateoka 3587 (P). Reg. Boeny [Prov. Mahajanga]: Bealoy, VI.1953, Bosser 5468 (P); 5–10 km before Ambondromamy, before Kamoro bridge, 13.II.2013, Vorontsova et al. 915 (K, TAN). Reg. DIANA [Prov. Antsiranana]: Ambavahibe, Montagne d'Ambre, VII.1953, Bosser 5515 (K, P); Nosy-Be, Ambatoloaka, VIII.1959, Bosser 13222 (P); Ambilobe, Sosumav, XII.1964, Morat 1284 (P); from Cape Ste Marie ANGAP office on the road to Soamanitra, 28.IV.2014, Vorontsova et al. 1432 (P, TAN).

  • 20. Urochloa eminii (Mez) Davidse in Monogr. Syst. Bot. Missouri Bot. Gard. 45: 1258. 1993.

  • Panicum eminii Mez in Bot. Jahrb. Syst. 34: 135. 1904.≡ Brachiaria eminii (Mez) Robyns in Bull. Jard. Bot. État Bruxelles 9: 176. 1932.

  • Lectotypus (designated by Robyns,1932: 177): Tanzania. Mwanza Reg.: Muansa, V.1892, Stuhlmann 4663 (B; isolecto-: BR [BR0000008756312] image!, K [K000282133]!).

  • = Brachiaria decumbens Stapf in Oliv., Fl. Trop. Afr. 9: 528.1919. ≡ Urochloa decumbens (Stapf) R.D. Webster, Austral. Paniceae: 234. 1987. Lectotypus (designated by Sosef, 2016: 360): Uganda. Kampala: Mengo Distr., Mpumu, X.1914, Dümmer 1070 (K [K000282130]!; isolecto-: BM [BM000923187]!, BOL [BOL139359] image!, BR [BR0000008639684] image!, PRE [PRE0664142-0] image!).

  • = Brachiaria ruziziensis R. Germ. & C.M. Evrard in Bull. Jard. Bot. État Bruxelles 23: 373. 1953. ≡ Urochloa ruziziensis (R. Germ. & C.M. Evrard) Crins in J. Arnold Arbor., Suppl. Ser. 1: 269. 1991. Holotypus: Democratic Republic of the Congo: plaine de la Ruzizi, Tsimuka, II.1950, Germain 6214 (BR [BR0000008756558] image!; iso-: EA [EA000000400] image!, YBI [YBI143266063] image!).

  • Stoloniferous perennial, largely erect, to 0.3–2 m high, culms weakly branched, rooting at lower nodes, glabrous to sparsely hirsute. Leaf sheath glabrous to pilose. Ligule a ciliate membrane. Leaf blade broadly linear to narrow-lanceolate, chartaceous, 5–20 × 0.7–1.5 cm, pilose on both sides. Inflorescence racemose, stout, open, 5–20 cm long. Racemes 2–7, 1–5 cm long, often curved, roughly even in length, on a common axis 1–8 cm long, with no secondary branching, rhachis subfoliaceous, 2–3.5 mm wide, margin ciliate with trichomes 1.5–3 mm long, spikelets imbricate, single, subsessile, usually in 2 rows. Spikelets plump elliptic to obovate, apically subacute, 4–5 mm long, white-yellowish, often with a purple tinge. Lower glume ⅓–½ as long as spikelet, membranous, clasping, acute or obtuse, 5-veined, glabrous, separated from rest of spikelet by a short internode, turned towards rhachis. Upper glume almost as long as spikelet, membranous, not shining, 5–7-veined, pubescent. Lower floret male, palea as long as lemma. Lower lemma membranous, not shining, 5–7-veined, pubescent. Upper lemma acute, smooth to finely rugulose, with a minute apical crest.

  • Distribution and ecology. – Introduced trial forage which does not seem to have gained widespread use or become naturalised; all known collections cite its introduced origin. Included here for completeness (Fig. 13).

  • Notes. – We follow Sosef (2016) and accept Urochloa eminii, U. decumbens (Stapf) R.D. Webster, and U. ruziziensis (R. Germ. & C.M. Evrard) Crins as representing a single species; all records known from Madagascar were previously placed in U. ruziziensis. Diagnostic characters of the known Malagasy specimens of U. eminii include herbaceous upper glume and lower lemma (shiny cartilaginous upper glume and lower lemma in U. brizantha), wide rhachis (narrow rhachis in U. brizantha), and stoloniferous habit (tufted habit in U. brizantha), although all of these intergrade into U. brizantha.

  • Additional specimens examined. – Madagascar. Reg. Alaotra-Mangoro [Prov. Toamasina]: introduit du Cogo Belge, Station Agricole Lac Alaotra, VI.1955, Bosser 8146 (P). Reg. Analamanga [Prov. Antananarivo]: Antananarivo Ville, Ivato, 16.IX.2000, Allorge 2531 (P). Reg. Bongolava [Prov. Antananarivo]: Kianjasoa, introduit, pasturage, 19.IV.1962, Boudet 1156 (P).

  • 21. Urochloa glumaris (Trin.) Veldkamp in Blumea 41: 420.1996.

  • Panicum glumare Trin., Gram. Panic. 143. 1826.

  • Holotypus: Country unknown: sine loco, s.d., Herb. Lindley in herb. Trinius 0727.01 (LE; iso-: CGE).

  • = Urochloa paspaloides J. Presl in C.B. Presl, Reliq. Haenk. 1: 318. 1830. ≡ Brachiaria paspaloides (J. Presl) C.E. Hubb., Hooker's Icon. Pl. 34: tab. 3363. 1938. Holotypus: Philippines: hab. in Luzonia ad Sorgozon, 1792, Haenke s.n. (PR; iso-: MO [MO-157629] image!, W [W0006080, W18890235852] image!).

  • Loosely tufted stoloniferous perennial, ascending to erect, 0.15–0.5 m high, culms sometimes branched at base, glabrous or pilose above, nodes bearded when young. Leaf sheath glabrous or sparsely pubescent towards apex, with ciliate margins. Ligule a ciliate membrane. Leaf blade linear, chartaceous, 5–20 × 0.3–0.8 cm, with tubercle-based hairs on both sides. Inflorescence racemose, slender, 5–10 cm long. Racemes 2–4, 2.5–6 cm long, roughly even in length, on a common axis 2–4 cm long, with no secondary branching, rhachis triquetrous, 0.5–0.8 mm wide becoming more narrow towards apex, finely pilose, spikelets overlapping untidily with adjacent spikelets, paired, sessile and shortly pedicelled in each pair. Spikelets elliptic, apically apiculate, 3.5–4.5 mm long, yellowish, often with a purple tinge. Lower glume ¾ to almost as long as spikelet, chartaceous, long-acuminate to mucronate, 5-veined, veins green, prominent, glabrous or scaberulous towards apex, turned away from rhachis. Upper glume as long as spikelet, somewhat concave, cartilaginous, long-acuminate, 7-veined, veins green, prominent, glabrous or scaberulous towards apex. Lower floret infertile, palea absent or minute. Lower lemma somewhat concave, cartilaginous, 5-veined, glabrous. Upper lemma rounded, rugulose, with a scabrous mucro 0.5 mm long.

  • Distribution and ecology. – Asian species long common in Mauritius, with only a single collection known from Madagascar: a historic Boivin collection from the Nosy Be island (and only a single collection known from La Reunion) (Fig. 15).

  • Notes. – Urochloa glumaris (Trin.) Veldkamp has acuminate to mucronate glumes, with the spikelet strongly dorsally compressed and a somewhat concave upper glume and lower lemma. Veldkamp (1996), Clayton et al. (2022), and Bosser & Renvoize (2018) record this species as annual but specimens suggest this is in fact a stoloniferous perennial sometimes branching at lower nodes.

  • For discussion of the typification see Veldkamp (1996).

  • Additional specimens examined. – Madagascar. Reg. DIANA [Prov. Antsiranana]: Nosy Be, s.d., Boivin 1978bis (P).

  • 22. Urochloa humbertiana (A. Camus) Voronts., comb. nov.

  • Brachiaria humbertiana A. Camus in Bull. Soc. Bot. France 79: 844. 1933.

  • Lectotypus (designated here): Madagascar. Reg. Atsimo-Andrefana [Prov. Toliara]: E du delta de la Linta, Beharahaka, VIII.1928, Humbert & Swingle 5487 (P [P00450180]!; isolecto-: P [P00450181]!). Syntypi: Madagascar. Reg. Androy [Prov.Toliara]: Ambovombe, II.1931, Decary 8466 (P [P02210586]!); Ambovombe, II.1931, Decary 8546 (K [K000805655]!; P [P02233594]!). Reg. Anosy [Prov. Toliara]: vallée du Mandrare à Amboasary, I.1932, Decary 9564 (P [P02210587]!). Reg. Atsimo-Andrefana [Prov. Toliara]: dunes de Tulear, V.1910, Perrier de la Bâthie 11188 (P [P02210588, P02233560]!).

  • Loosely tufted perennial, with short knotty rhizomes, ascending to erect, to 0.5 m high, culms branched at base, rooting at lower nodes, glabrous to shortly pilose. Leaf sheath glabrous or sometimes pilose. Ligule a lacerate ciliolate membrane. Leaf blade linear, sometimes narrow-lanceolate, chartaceous, 2.5–10 × 0.1–0.5 cm, glabrous to pubescent on both sides. Inflorescence racemose, slender, open or contracted, 5–10 cm long. Racemes 3–7, 1–5 cm long, flexuous, decreasing in length upwards, lowermost raceme roughly equal to inflorescence axis in length, on a common axis 2–6 cm long, with no secondary branching, rhachis narrow, scabrous, spikelets not overlapping with adjacent spikelets, single, on pedicels of uneven length. Spikelets oblong to somewhat obovate, apically subacute, 2–3 mm long, whiteish. Lower glume c. ⅓ as long as spikelet, membranous, obtuse, 1–3-veined, glabrous or sometimes pilose, separated from rest of spikelet by an internode c. 0.5 mm long, orientation relative to rhachis variable. Upper glume as long as spikelet, herbaceous, 5-veined, veins dark green, glabrous or sometimes pilose. Lower floret infertile or male, palea c. ⅔ to as long as lemma, anthers 3, c. 2 mm long. Lower lemma herbaceous, 5-veined, glabrous or sometimes pilose. Upper lemma subacute, finely rugose to almost smooth.

  • Distribution and ecology. – Endemic to southern Madagascar and abundant in southern spiny forest, in both primary and secondary vegetation, at elevations of 0–750 m. Frequently found on dunes by the sea (Fig. 15).

  • Notes. – Urochloa humbertiana (A. Camus) Voronts. can usually be recognised by its unusually narrow linear leaf blades 1–3 mm wide; these sometimes become lanceolate up to 5 mm wide. Its lower glume is translucent with almost invisible veins, while the 5 veins on upper glume and the lower lemma are a clearly visible dark green colour. The species U. humbertiana encompasses considerable variability in leaf width (usually narrow and linear, sometimes broader and narrow-lanceolate), indumentum (leaf blades and spikelets usually glabrous but sometimes pilose), and fertility of the lower floret (usually sterile with palea c. ⅔ as long as the lower lemma, sometimes male with 3 anthers and palea as long as the lemma). Individuals with broad leaf blades, indumentum, and fertile lower florets (e.g. Bosser 14626 and Nanjarisoa et al. 192) are substantially different in appearance but do not seem to justify the description of a new species.

  • The lectotype is chosen for its superior quality material and annotation by the author.

  • Selected specimens examined. – Madagascar. Reg. Androy [Prov. Toliara]: Beloha, III.1960, Bosser 14149 (P). Reg. Anosy [Prov. Toliara]: vallée de la Manambolo au NW de Maroaomby, XII.1933, Humbert 12771 (K, P, TAN). Reg. Atsimo-Andrefana [Prov. Toliara]: 32 km au N de Tuléar, Madiorano, forêt de M. Domergue, 31.I.1990, Labat & Du Puy 2037 (K, P); plateau Mahafaly, s.d., Perrier de la Bâthie 115 (K); Berenty, 10 km from Amboasary west, 16.III.2019, Rakotomalala et al. 289 (K, TAN).

  • Fig. 15.

    Distribution maps. Urochloa glumaris (Trin.) Veldkamp (stars), U. humbertiana (A. Camus) Voronts. (triangles), U. jubata (Fig. & De Not.) Sosef (circles), and U. mutica (Forssk.) T.Q. Nguyen (squares).

    img-z30-1_199.jpg

    23. Urochloa jubata (Fig. & De Not.) Sosef, Fl. Gabon 5bis: 64. 1999.

  • Panicum jubatum Fig. & De Not. in Agrost. Aegypt. Fragm. 2: 15. 1853. ≡ Brachiaria jubata (Fig. & De Not.) Stapf in Oliv., Fl. Trop. Afr. 9: 563. 1919.

  • Holotypus: Sudan: Cordofan, s.d., Figari s.n. (FI).

  • Tufted perennial, erect, 0.25–1.2 m high, culms not branched, glabrous. Leaf sheath glabrous. Ligule a ciliate membrane. Leaf blade broadly linear, chartaceous, 5–30 × 0.3–1.7 cm, glabrous on both sides, with bulbous based trichomes on margins at base. Inflorescence racemose, slender, contracted, 5–25 cm long. Racemes 5–10, 1–6 cm long, often curved, on a common axis 3–20 cm long, with no secondary branching, rhachis winged, 1–2 mm wide, margin ciliate with yellow tubercle-based trichomes 2–6 mm long, spikelets imbricate, single, subsessile, in 2 rows. Spikelets elliptic, apically subacute, 2.5–3.8 mm long, yellowish, often with a purple tinge. Lower glume ⅔–¾ as long as spikelet, membranous, apically rounded, 7–11-veined, glabrous, turned towards rhachis. Upper glume as long as spikelet, membranous, 5–7-veined, pubescent. Lower floret male, palea as long as lemma, anthers 3, c. 1.5 mm long. Lower lemma membranous, 5-veined, with a few cross veins, pubescent. Upper lemma subacute, rugulose, shiny, with a minute apical crest.

  • Distribution and ecology. – This African species seems to be an isolated experimental forage introduction to Madagascar. It has not been seen since the only known collection (Fig. 15).

  • Notes. – Urochloa jubata can be readily recognised by the yellow cilia on the edges of the rhachis, and long rounded lower glume with 7–11 veins.

  • Additional specimens examined. – Madagascar. Reg. Itasy [Prov. Antananarivo]: vallée de l'Isaonjo, 10–15 km W d'Ambohitrombo, V.1964, Groene s.n. (TAN, P).

  • 24. Urochloa mutica (Forssk.) T.Q. Nguyen in Novosti Sist. Vyssh. Rast. 1966: 13. 1966.

  • Panicum muticum Forssk., Fl. Aegypt.-Arab. 20. 1775. ≡ Brachiaria mutica (Forssk.) Stapf in Oliv., Fl. Trop. Afr. 9: 526. 1919.

  • Holotypus: Egypt. Beheira: Rashid, XI.1761, Forsskål 86 (C [C10002726] image!; iso-: BM).

  • Stoloniferous perennial, ascending to erect, 0.25–1.25 m high, culms weakly branched, rooting at lower nodes, glabrous, nodes prominently bearded. Leaf sheath glabrous to pubescent. Ligule a line of hairs. Leaf blade linear, thickly chartaceous, 6–30 × 0.3–1.5 cm, glabrous to pubescent on both sides. Inflorescence racemose, pyramidal, open, 10–30 cm long. Racemes 5–20, 2–10 cm long, decreasing in length upwards, on a common axis 7–20 cm long, with short secondary branches on lower racemes, rhachis narrowly winged, 0.5–1 mm wide, scabrid, spikelets overlapping with adjacent spikelets, paired near base and single towards apex of racemes, subsessile, in several untidy rows, subtended by a few cilia. Spikelets elliptic, apically acute to acuminate, 2.5–3.5 mm long, yellowish to purple. Lower glume ¼–⅓ as long as spikelet, membranous, acute, 1–3-veined, glabrous, orientation relative to rhachis variable. Upper glume as long as spikelet, membranous, 5–7-veined, glabrous. Lower floret male, palea as long as lemma, anthers 3, c. 1.8 mm long. Lower lemma membranous, 5-veined, glabrous. Upper lemma obtuse, rugulose, minutely mucronate.

  • Distribution and ecology. – The origin of this easily recognisable pantropical forage is not fully clear. At least some of the known localities are introductions; Boivin recorded it as “naturalised” on Mauritius in 1851 [P06769193]. Damp habitats in fields and secondary vegetation (Fig. 15).

  • Notes. – Urochloa mutica is recognised by its tall stature and its pyramidal inflorescences with an untidy arrangement of spikelets on the racemes.

  • Selected specimens examined. – Madagascar. Reg. Sofia [Prov. Mahajanga]: Bealanana, Betainkankana, Ankaizina, V.1952, Bosser 2557 (P). Reg. Boeny [Prov. Mahajanga]: Mahajanga Ville, Amborovy, 8.V.1962, Boudet 1277 (P); Marovoay, IMVPT 890, 9.V.1962, Boudet 4283 (P). Reg. Alaotra-Mangoro [Prov. Toamasina]: Ambatondrazaka, introduced, 7.III.1932, Jard. Bot. Tananarive 324119 (P).

  • 25. Urochloa nana (Stapf) Voronts., comb. nov.

  • Brachiaria nana Stapf in Bull. Misc. Inform. Kew 1919: 264. 1919.

  • Holotypus: Madagascar. Reg. Atsimo-Andrefana [Prov. Toliara]: Onilahy, near Sakomdy river, VI.1910, Perrier de la Bâthie 117 [“107”] or 11202 (K [K000244719]!; iso-: P [P00450185, P00450186]!).

  • Loosely tufted stoloniferous perennial, ascending to erect, to 20 cm high, culms much branched, rooting at lower nodes, culms glabrous or pubescent, nodes finely hirsute. Leaf sheath glabrous or sparsely pubescent with ciliate margins. Ligule a line of hairs. Leaf blade ovate, basally cordate, thickly chartaceous, 1–4 × 0.4–1 cm, glabrous to sparsely hirsute on both sides, sometimes with bulbous-based trichomes near base. Inflorescence racemose, contracted or sometimes open, rarely fully exserted, 3–5 cm long. Racemes 3–5, 2–3 cm long, roughly even in length, often appressed, frequently bare towards apex on a common axis 0.5–1.5 cm long, with no secondary branching, rhachis triquetrous to narrowly winged, 0.6–0.8 mm wide, scaberulous, spikelets overlapping untidily with adjacent spikelets, paired, subsessile, in 2 untidy rows. Spikelets elliptic, apically apiculate, 2.7–3 mm long, whiteish. Lower glume ¼–⅓ as long as spikelet, membranous, obtuse to acute, 1–3-veined, glabrous, orientation relative to rhachis variable. Upper glume as long as spikelet, membranous, 5–7-veined, with cross veins towards apex, glabrous. Lower floret infertile, palea absent or ⅓–½ as long as lemma. Lower lemma membranous, 5–7-veined, with cross veins towards apex, glabrous. Upper lemma obtuse, rugulose.

  • Distribution and ecology. – Endemic to the northern, western, and southern parts of Madagascar. Dry forest and spiny forest and savanna, roadsides, cultivation, often on limestone, at elevations of 0–800 m (Fig. 16).

  • Notes. – Urochloa nana can be recognised by its visibly thick leaf blades, and frequently bare apices of racemes. It is somewhat similar to U. ramosa but its spikelets are smaller, upper lemma less rugose, lower glume more membranous, and its leaf blades thicker. Urochloa nana also resembles U. reptans (L.) Stapf with its leaf blades and racemes crowded at the apex of the culms and slightly curved upwards; U. nana can be distinguished from U. reptans by its larger spikelets, a 3-veined lower glume, and the absence of a mucro on the upper lemma. Urochloa nana seems to be related to U. distachyos as its chloroplast DNA sequences were identical (Hackel et al., 2018).

  • The collection series of Perrier de la Bâthie are labelled with five-digit numbers at P, with duplicates of the same series marked with three-digit numbers at K. It is sometimes possible to establish a correspondence between these two series when both numbers are cross-referenced on a sheet at P, such as the isotype sheet P00450185. Thus, the type collection is marked with two alternative numbers: Perrier de la Bâthie 117 and 11202. It seems clear the number 107 in the protologue is an error, because the holotype sheet is numbered 117, annotated by Oto Stapf, and is the only historic collection of this species held at K.

  • Selected specimens examined. – Madagascar. Reg. Atsimo-Andrefana [Prov. Toliara]: Sakaraha, II.1956, Bosser 9000 (P); Sakaraha, forêt de Zombitsy, III.1955, Humbert et al. 29663 (P); Morondava Airport, 9.III.1953, Porteres s.n. (P). Reg. DIANA [Prov. Antsiranana]: Ambilobe, Sosumav, XII.1964, Morat 1271 (P); Andrafiabe, Ankarana, I.1969, Morat 3111 (P). Reg. Melaky [Prov. Mahajanga]: lisière de la R.N. 9, Antsalova, I.1975, Morat 4851 (P). Reg. SAVA [Prov. Antsiranana]: Sambava, Marojejy NP office, 14.X.2011, Hall et al. 28 (K, TAN).

  • 26. Urochloa panicoides P. Beauv., Ess. Agrostogr.: 52, tab. 11. 1812.

  • Panicum panicoides (P. Beauv.) Hitchc. in J. Washington Acad. Sci. 9: 551. 1919.

  • Lectotypus (designated by Veldkamp, 1996: 433): [icon] (Beauvois, Ess. Agrostogr.: 52, tab. 11. 1812).

  • Loosely tufted annual, ascending to erect, 0.1–1 m high, culms not branched, rooting at lower nodes, glabrous. Leaf sheath glabrous or sparsely pilose, with ciliate margins. Ligule a ciliate membrane. Leaf blade broadly linear to narrow-lanceolate, chartaceous, 2–25 × 0.5–1.8 cm, glabrous or sparsely pilose on both sides, with bulbous based trichomes on margins at base. Inflorescence racemose, thick, 5–10 cm long. Racemes 2–7, 1–7 cm long, roughly even in length, on a common axis 1–9 cm long, with no secondary branching, rhachis narrowly winged, 0.8–1.3 mm wide, smooth with pilose margins, spikelets imbricate, single or paired, subsessile, subtended by a few long cilia. Spikelets elliptic, apically acute, 3.5–4.5 mm long, drying yellow-green. Lower glume ¼–⅓ as long as spikelet, membranous, ovate, obtuse to subacute, 3–5-veined, glabrous or pubescent, turned away from rhachis. Upper glume as long as spikelet, somewhat concave, membranous, acute, 7-veined, veins green, prominent, with cross veins sometimes visible, glabrous or pubescent. Lower floret infertile, palea absent. Lower lemma somewhat concave, membranous, 7-veined, with cross veins sometimes visible, glabrous or pubescent, sometimes with a setose fringe. Upper lemma rounded, rugulose, with a mucro 0.3–1 mm long.

  • Distribution and ecology. – Until 2012 this paleotropical forage and invasive savanna grass common in the Mascarenes was only known in Madagascar from a single collection; it is not clear whether it has previously been overlooked or whether it is undergoing a period of spread. According to recent observations, it is often locally common. Open secondary vegetation on sand, beaches and roadsides, spiny forest understory, at elevations of 0–150 m (Fig. 16).

  • Notes. – The spikelets of Urochloa panicoides P. Beauv. can be either glabrous or pubescent. Its somewhat concave upper glume and lower lemma are similar to U. glumaris.

  • Additional specimens examined. – Madagascar. Reg. Atsimo-Andrefana [Prov. Toliara]: Sakaraha, 3 km S du village de Mahaboboka, 20.IV.2014, Nanjarisoa et al. 176 (K, TAN). Reg. Boeny [Prov. Mahajanga]: Ambalakida, c. 5 km before Andradia on the track from Majunga-Ankarafantsika road towards Anjohibe cave, 16.II.2013, Vorontsova et al. 955 (K, TAN). Reg. DIANA [Prov. Antsiranana]: extremitè nord du Cap d'Ambre, VIII.1955, Gillard s.n. (P); Ankarana MNP office, 28.II.2015, Vorontsova et al. 1829 (K, TAN); Antsiranana city, 2.III.2015, Vorontsova et al. 1833 (K, TAN).

  • Fig. 16.

    Distribution maps. Urochloa nana (Stapf) Voronts. (stars), U. panicoides P. Beauv. (triangles), U. plantaginea (Link) R.D. Webster (circles), and U. pseudodichotoma (Bosser) Voronts. (squares).

    img-z32-9_199.jpg

    27. Urochloa plantaginea (Link) R.D. Webster in Syst. Bot. 13: 607. 1988.

  • Panicum plantagineum Link, Hort. Berol. 1: 206. 1827 [non P. plantagineum Schumach., 1827] [nom. illeg.]. ≡ Brachiaria plantaginea (Link) Hitchc. in Contr. U.S. Natl. Herb. 12: 212. 1909. Holotypus: [Brazil]: cultivated in the Berlin Botanical Gardens, Anon. s.n. (B [B 10 0367300] image!; iso-: HAL [HAL0082173] image!, US [US00139874 fragm.]!).

  • Loosely tufted stoloniferous perennial, ascending to erect, 0.4–1 m high, culms weakly branched, rooting at lower nodes, glabrous. Leaf sheath glabrous. Ligule a line of hairs. Leaf blade lanceolate, chartaceous, 4–21 × 0.6–1.3 cm, glabrous to pubescent on both sides. Inflorescence racemose, stout, open, 10–30 cm long. Racemes 2–8, 2–11 cm long, gently curved, roughly even in length, on a common axis 10–20 cm long, with no secondary branching, rhachis winged, 1–2 mm wide, scaberulous, spikelets imbricate, single, subsessile, in 2 rows. Spikelets elliptic, apically acute, 4–5.5 mm long, yellowish. Lower glume ¼–⅓ as long as spikelet, membranous, clasping, obtuse to acute, 3–5-veined, glabrous, separated from rest of spikelet by an internode c. 0.5 mm long, turned towards rhachis. Upper glume as long as spikelet, membranous, 5–7-veined, glabrous. Lower floret infertile or male, palea ⅔ to as long as lemma. Lower lemma membranous, 5-veined, glabrous. Upper lemma subacute, rugulose, sometimes with a minute mucro.

  • Distribution and ecology. – This highly competitive weedy grass from South America has been introduced to North America and to West Africa. A single collection is known from Madagascar (Fig. 16).

  • Notes. – Urochloa plantaginea (Link) R.D. Webster appears similar to U. arrecta but has a significantly larger spikelet.

  • The illegitimate homonym Panicum plantagineum Schumach. is a synonym of the easy to distinguish P. brevifolium L. Additional specimen examined. – Madagascar. Reg. Sofia [Prov. Mahajanga]: Bealanana, Betainkankana, Ankaizina, V.1952, Bosser 2803 (P).

  • 28. Urochloa pseudodichotoma (Bosser) Voronts., comb. nov.

  • Brachiaria pseudodichotoma Bosser in Adansonia, sér. 2, 6: 109. 1966.

  • Holotypus: Madagascar. Reg. Atsimo-Andrefana [Prov. Toliara]: Anavoha, secteur de Fotadrevo poste d'Ejeda, 17.II.1960, Dauban s.n. (P [P00450189]!).

  • Mat-forming annual to short-lived stoloniferous perennial, prostrate with ascending flowering culms, to 10 cm high, culms branching at every node, rooting at lower nodes, glabrous, nodes finely hirsute. Leaf sheath glabrous or sparsely pubescent with ciliate margins. Ligule a line of hairs. Leaf blade ovate, flat or sometimes folded, chartaceous, 1–2 × 0.05–0.4 cm, drying somewhat glaucous, glabrous on both sides. Inflorescence racemose, slender, contracted, partly exserted, 1–2 cm long. Racemes 1–2, 0.8–1.5 cm long, roughly even in length, with no secondary branching, rhachis narrowly winged, 0.5–0.8 mm wide, scaberulous, spikelets imbricate, single, subsessile, in 2 tidy rows. Spikelets elliptic, apically apiculate, 2–2.5 mm long, whiteish. Lower glume c. ¼ as long as spikelet, membranous, usually obtuse, 1–3-veined, glabrous, overlapping on opposite side of spikelet, turned towards rhachis. Upper glume as long as spikelet, membranous, 5–7-veined, with cross veins towards apex, glabrous. Lower floret infertile, palea absent. Lower lemma membranous, 5–7-veined, with cross veins towards apex, glabrous. Upper lemma obtuse, rugulose.

  • Distribution and ecology. – Endemic to western and southern Madagascar, with a single record from Antananarivo (Perrier 10886 locality is questioned in a note by Bosser). Open savanna and secondary vegetation on sand, spiny forest understory, disturbed areas, at elevations of 0–200m (1200 m if the Antananarivo record is correct) (Fig. 16).

  • Notes. – Urochloa pseudodichotoma (Bosser) Voronts. forms visually appealing spreading mats. The unusual feature of this species is dichotomous branching at each culm node, so all leaf blades are on secondary branches.

  • Selected specimens examined. – Madagascar. Reg. Analamanga [Prov. Antananarivo]: Antananarivo-ville, I.1915, Perrier de la Bâthie 10886 (P). Reg. Anosy [Prov. Toliara]: Atsimo-Andrefana, entre Ampanihy et Ejeda, XI.1956, Bosser 10109 (P); Amboasary-Sud, Somangy, c. 8 km from Amboasary to Berenty, 15.III.2019, Rakotomalala et al. 268 (K, TAN). Reg. Atsimo-Andrefana [Prov. Toliara]: near Beza Mahafaly Reserve, Ambinda stream, 15.I.1989, Phillipson & Rabesihanaka 3180 (K, P). Reg. Boeny [Prov. Mahajanga]: près de Marovoay, V.1927, Perrier de la Bâthie 17964 (P); Station Forestière Antsianitia, 15.II.2013, Vorontsova et al. 942 (K, TAN). Reg. DIANA [Prov. Antsiranana]: Mahomasina, bungalows near MNP Ankarana office, 26.II.2015, Vorontsova et al. 1814 (K, P, TAN). Reg. Sofia [Prov. Mahajanga]: nord du Bongolava, sud de Port Berge, IV.1967, Morat 2718 (P).

  • 29. Urochloa ramosa (L.) T.Q. Nguyen in Novosti Sist. Vyssh. Rast. 1966: 13. 1966.

  • Panicum ramosum L., Mant. Pl. 1: 29. 1767. ≡ Brachiaria ramosa (L.) Stapf in Oliv., Fl. Trop. Afr. 9: 542. 1919.

  • Lectotypus (designated by Cope in Nasir & Ali, 1982: 207): [India]: cultivated in Uppsala (Sweden), Anon. s.n. (LINN-HL n°80–44 image!).

  • Loosely tufted annual, ascending to erect, 0.1–0.7 m high, culms weakly branched, glabrous. Leaf sheath glabrous to pubescent. Ligule a line of hairs. Leaf blade lanceolate, chartaceous, 2–25 × 0.4–1.4 cm, glabrous to pubescent on both sides. Inflorescence racemose, open, 6–15 cm long. Racemes 3–15, 1–8 cm long, flexuous, decreasing in length upwards, on a common axis 3–10 cm long, sometimes with small secondary branches at base, rhachis triquetrous, scaberulous, spikelets mostly not overlapping with adjacent spikelets, single, on pedicels of uneven length, pedicels shorter than spikelets, subtended by white cilia. Spikelets broadly elliptic, plump, apiculate, 2.5–3.5 mm long, yellowish. Lower glume ⅓–½ as long as spikelet, membranous, clasping, obtuse to acute, 5–7-veined, cross veins visible, glabrous, sometimes separated from rest of spikelet by an internode c. 0.5 mm long, orientation relative to rhachis variable. Upper glume almost as long as spikelet, membranous, 5–7-veined, cross veins visible, glabrous or sometimes pubescent. Lower floret infertile, palea ⅔–¾ as long as lemma. Lower lemma membranous or somerimes coriaceous, 5-veined, cross veins sometimes visible, glabrous or sometimes pubescent. Upper lemma subacute to acute, rugose.

  • Distribution and ecology. – The origin of this African and Asian grass in Madagascar remains unknown. In Madagascar it occurs largely in the west; open grassland, cultivation, roadsides, and seashores, at low elevations (Fig. 17).

  • Notes. – Urochloa ramosa can be recognised by its plump spikelets. Its racemes appear to have a “messy-looking” arrangement due to paired spikelets with pedicels of different lengths partly overlapping: this is similar to the “messy” racemes of U. nana, U. reptans, and U. mutica but unlike the more “tidy-looking” racemes of U. distachyos and U. arrecta where pedicels are uniform. According to Clayton & Renvoize (1982) and Clayton (1989), U. ramosa is doubtfully distinct from U. deflexa; the two indeed look similar, but U. ramosa can be distinguished by its shorter pedicels.

  • According to the Linnean typification project [ https://www.nhm.ac.uk/our-science/data/linnaean-typification]: “The typification of this name is attributable to Cope (June 1982), who published it some months ahead of Clayton & Renvoize (in Polhill, Fl. Trop. E. Africa, Gramineae 3: 599. 5 November 1982).”

  • Selected specimens examined. – Madagascar. Reg. Alaotra-Mangoro [Prov. Toamasina]: Ambatovy forest, Analamay, 1.III.2005, Antilahimena & Razafindasy 3511 (P); Alaotra Lake, Herbier de la Station Agricole de l' Alaotra 27014 (P). Reg. Androy [Prov. Toliara]: Ambovombe-Androy, Talaky centre, c. 3 km from Ambovombe town to southeast, 17.III.2019, Rakotomalala et al. 302 (K, TAN). Reg. Atsimo-Andrefana [Prov. Toliara]: Tulear, Perrier de la Bâthie 131 (K). Reg. Boeny [Prov. Mahajanga]: Mahajanga ville, Pointe du Caïman, 12.I.1929, Humbert 7155 (P). Reg. DIANA [Prov. Antsiranana]: extrême nord du Cap d'Ambre, VIII.1955, Gillard s.n. (P); chemins près d'Antsirane, 13.IX.1912, Viguier & Humbert 140 (P). Reg. Sofia [Prov. Mahajanga]: Mampikony to Ambanja, Analamisakana area, 21.II.2015, Vorontsova et al. 1764 (K, TAN).

  • 30. Urochloa reptans (L.) Stapf in Oliv., Fl. Trop. Afr. 9: 601. 1920 (Fig. 14E–F).

  • Panicum reptans L., Syst. Nat. ed. 10, 2: 870. 1759. ≡ Brachiaria reptans (L.) C.A. Gardner & C.E. Hubb., Hooker's Icon. Pl. 34: tab. 3363. 1938.

  • Lectotypus (first step designated by Hitchcock & Chase, 1910: 36; second step designated by Veldkamp, 1996: 427): Country unknown: sine loco, Browne s.n., Herb. Linn. No. 80.52, upper specimen (LINN-HL80-52 image!).

  • Annual to short-lived stoloniferous perennial, ascending to erect, to 0.6 m high, culms weakly branched, rooting at lower nodes, glabrous or pubescent, nodes finely hirsute. Leaf sheath glabrous or sparsely pubescent with ciliate margins. Ligule a line of hairs. Leaf blade ovate to lanceolate, basally cordate, chartaceous, 1–6 × 0.3–1.2 cm, glabrous to sparsely hirsute on both sides, sometimes with bulbous-based trichomes near base. Inflorescence racemose, slender, open or contracted, 3–5 cm long. Racemes 4–15, 1–3.5 cm long, decreasing in length upwards on a common axis 1–3 cm long, sometimes with secondary branchlets, rhachis triquetrous, less than 0.5 mm wide, scaberulous to pubescent, spikelets overlapping untidily with adjacent spikelets, single, on pedicels of uneven length, subtended by white cilia. Spikelets ovate, apically acute, 1.7–2 mm long, yellow-brown to purpleish. Lower glume c. ¼ as long as spikelet, membranous, truncate, with no veins, glabrous, orientation relative to rhachis variable. Upper glume as long as spikelet, membranous, 5–7-veined, glabrous. Lower floret infertile, palea as long as lemma. Lower lemma membranous, 5–7-veined, glabrous. Upper lemma rounded, rugulose, mucronate.

  • Distribution and ecology. – Pantropical known weed with Malagasy populations of unknown origin. West Madagascar, especially abundant in north Madagascar where it often forms a dominant contribution to grazing lawn turf. Coastal grasslands and grazing lawns, secondary vegetation and roadsides, dry forest understory, often on sand, at elevations of 0–300 m (Fig. 17).

  • Notes. – The young inflorescences of Urochloa reptans are frequently purple in a way not usually seen in other species. Urochloa reptans displays a remarkable range of sizes, with smaller plants that appear reproductively immature still capable of producing clearly separated and reproductively functional spikelets on apical racemes.The mucro on the upper lemma appears to be sometimes absent.

  • According to the Linnean typification project [ https://www.nhm.ac.uk/our-science/data/linnaean-typification]: “Veldkamp (in Blumea 41: 429. 1996) followed Hitchcock (in Contr. U. S. Natl. Herb. 12: 119. 1908) in regarding this and P. reptans L. (1759) as homotypic. However, the first clear type choice dates from Hitchcock & Chase (in Contr. U. S. Natl. Herb. 15: 36. 1910), later restricted to the upper specimen on the sheet by Veldkamp”.

  • Selected specimens examined. – Madagascar. Reg. Atsimo-Andrefana [Prov. Toliara]: vallée du Fiherenana, III.1960, Bosser 14019 (P); Ankazoabo-Sud, Fotivolo, II.1963, Bosser 17952 (P). Reg. Boeny [Prov. Mahajanga]: Ambato Boeny, XI.1951, Bosser 2012 (K, P); Androhibe, I.1967, Granier & Delhaye 112 (P); Basalle - Antanimena plateu, I.1924, Perrier de la Bâthie 15919 (P). Reg. Diana [Prov. Antsiranana]: Nosy Be, IV.1879, Hildebrandt 2928 (K, P); commune Antsahampano, fokontany Antongombato, Antamotamo, 3.III.2015, Vorontsova et al. 1840 (TAN). Reg. SAVA [Prov. Antsiranana]: Vohemar, Daraina Protected Area office grounds, 12.X.2011, Vorontsova et al. 352 (K, TAN); outside Montagne d'Ambre Parcelle 1. Reg. Sofia [Prov. Mahajanga]: Moramandia, Andranosamantana, 28.II.1923, Decary 1468 (P).

  • Fig. 17.

    Distribution maps. Urochloa ramosa (L.) T.Q. Nguyen (stars), U. reptans (L.) Stapf (triangles), and U. trichopus (Hochst.) Stapf (circles).

    img-z35-1_199.jpg

    31. Urochloa trichopus (Hochst.) Stapf in Oliv., Fl. Trop. Afr. 9: 589. 1920.

  • Panicum trichopus Hochst. in Flora 27: 254. 1844.

  • Holotypus: [Sudan]: cultivated in Cordofan, 1837, Kotschy 74 (TUB ([TUB006436] image!); iso-: BM ([BM000923215, BM000923216]!), G ([G00022708] image!), K [K000281979, K000281980]!, MO [MO-1660898] image!, S [S05-8793] image!, US [US-1125963]!, W [W0030715, W0030714, W18890243303, W19160023511] image!).

  • = Urochloa mosambicensis (Hack.) Dandy in J. Bot. 69: 54. 1931. ≡ Panicum mosambicense Hack. in Bol. Soc. Brot. 6: 140. 1888. Holotypus: Mozambique: continente fronteiro, 1884, de Carvalho 19 (W [W19160023605] image!; iso-: COI, K [K000281991]!).

  • Loosely tufted stoloniferous perennial, ascending to erect, to 0.2–1.5 m high, culms not branched, glabrous, nodes bearded, basal sheaths silky pubescent. Leaf sheath glabrous or sparsely pubescent towards apex, with ciliate margins. Ligule a line of hairs. Leaf blade broadly linear to narrow-lanceolate, chartaceous, 2–30 × 0.3–2 cm, sparsely to densely pilose on both sides. Inflorescence racemose, thick, 7–20 cm long. Racemes 3–15, 2–8 cm long, roughly even in length, on a common axis 3–12 cm long, with no secondary branching, rhachis narrowly winged, 0.8–1 mm wide, scaberulous to finely pilose, spikelets imbricate, single or paired, subsessile, subtended by a few long cilia. Spikelets ovate, plump, apically acuminate, 3–5 mm long, drying yellowish with silky-white hairs. Lower glume ⅔–¾ as long as spikelet, membranous, obtuse, 3(–5)-veined, side veins joining midvein near apex, often with a tuft of hairs from middle of back, turned away from rhachis. Upper glume as long as spikelet, membranous, long-acuminate, 7-veined, glabrous or pubescent. Lower floret male, palea as long as lemma, anthers 3, 1.5–2 mm long. Lower lemma membranous, long-acuminate with central nerve developing into a mucro, 5-veined, with cross veins towards apex, usually with a setose fringe. Upper lemma rounded, rugulose, with a mucro 0.5–1.2 mm long.

  • Distribution and ecology. – African species not present in the Mascarenes; only two localities are currently known from the western coast but it is likely the true distribution is more widespread. Not clear whether this species is native to Madagascar. Open secondary vegetation on sand, roadsides, at low elevations (Fig. 17).

  • Notes. – Distinctive by its odd obtuse lower glume with tuft of trichomes in the middle. Appears to be polyphyletic in Hackel et al. (2018). The accession Vorontsova et al. 916 yielded three chloroplast regions which place it as sister to the African and Asian clade containing Urochloa reptans, U. glumaris, U. ramosa, U. praetervisa (Domin) Hughes, U. echinolaenoides Stapf, and U. setigera (Retz.) Stapf. Only one of these regions, ndhF, was available for the second accession from Kruger National Park, South Africa (YBK350 from Bouchenak-Khelladi et al., 2014) and the species was recovered as part of an African clade with U. rudis Stapf and U. panicoides. Good forage (Bosser, 1969).

  • Additional specimens examined. – Madagascar. Reg. Boeny [Prov. Mahajanga]: La Corniche, Kanto Hotel grounds, 14.II.2013, Vorontsova et al. 916 (K, TAN). Reg. Melaky [Prov. Mahajanga]: env. de Maintirano, II.1957, Service Veterinaire s.n. (P); ibid. loco, X.1964, Morat 732 (P, TAN).

  • Acknowledgements

    The author would like to thank the SYNTHESYS scheme and the Bentham-Moxon Trust for supporting the author's visits to P, and the curators of K, P, and TAN herbaria for access to their collections. Thank you to Lucy T. Smith (RBG Kew), Sarah Z. Ficinski (RBG Kew), and Roger Lala Andriamiarisoa (Missouri Botanical Garden, Madagascar) for the beautiful drawings and maps. Thank you to staff of the Virtual Herbarium Berolinense Botanischer Garten und Botanisches Museum Berlin (B) for digital specimen loans and especially Robert Vogt and Katherina Rabe, and to Robert Soreng (Smithsonian Institution) for adding type information to tropicos.org. Thank you to Guillaume Besnard (CNRS-Toulouse) and Jan Hackel (RBG Kew) for the phylogenetic and phylogenomic analysis.

    References

    1.

    Baker, J.G. (1877). Flora of Mauritius and the Seychelles: a description of the flowering plants and ferns of those islands. L. Reeve, London. Google Scholar

    2.

    Bogdan, A.V. (1977). Tropical pasture and fodder plants. Longman, London. Google Scholar

    3.

    Bosser, J. (1966). Notes sur les graminées de Madagascar III. Adansonia, sér. 2, 6: 105–112. Google Scholar

    4.

    Bosser, J. (1969). Graminées des pâturages et des cultures à Madagascar. Mémoire Orstom 35. Antananarivo. Google Scholar

    5.

    Bosser, J. & S. Renvoize (2018). Graminées. In : Autrey, J.C. et al. (ed.), Fl. Mascareignes 203. IRD Editions, Marseille. Google Scholar

    6.

    Cafferty, S., C.E. Jarvis & N.J. Turland (2000). Typification of Linnaean plant names in the Poaceae (Gramineae). Taxon 49: 239–260. Google Scholar

    7.

    Camus, A. (1925). Sacciolepis, Panicum, Brachiaria et Boivinella nouveaux de Madagascar et des Comores. Bull. Soc. Bot. France 72: 618–623. Google Scholar

    8.

    Camus, A. (1935). Brachiaria fragrans A. Camus, graminée nouvelle de Madagascar. Bull. Soc. Bot. France 82: 22. Google Scholar

    9.

    Camus, A. (1947). Graminées nouvelles de Madagascar. Bull. Soc. Bot. France 94: 39–42. Google Scholar

    10.

    Camus, A. (1950). Sur deux graminées de Madagascar. Bull. Mus. Natl. Hist. Nat., sér. 2, 22: 296–297. Google Scholar

    11.

    Camus, A. (1954). Acroceras, Brachiaria et Setaria nouveaux de Madagascar. Bull. Soc. Bot. France 101: 28–30. Google Scholar

    12.

    Camus, A. (1957). Contribution a l'étude des graminées de Madagascar. Bull. Mus. Natl. Hist. Nat., sér. 2, 29: 274–281. Google Scholar

    13.

    Clayton, W.D. (1989). Gramineae. In : Launert, E. & G.V. Pope (ed.), Fl. Zambesiaca 10(3). Royal Botanic Gardens, Kew. Google Scholar

    14.

    Clayton, W.D. & S.A. Renvoize (1982). Gramineae (Part 3). In : Turrill, W.B. & R.M. Polhill (ed.), Fl. Trop. E. Africa : 451–898. A.A. Balkema, Rotterdam. Google Scholar

    15.

    Clayton, W. D., M. S. Vorontsova, K. T. Harman & H. Williamson (2022). GrassBase – The online world grass flora. The Board of Trustees, Royal Botanic Gardens, Kew. [  https://www.kew.org/data/grassbase/index.htmlGoogle Scholar

    16.

    Cope, T.A. (1982). Poaceae. In : E. Nasir & S.I. Ali (ed.), Fl. Pakistan 143. Pakistan Agricultural Research Council and University of Karachi, Islamabad and Karachi. Google Scholar

    17.

    Fish, L., A.C. Mashau, M.J. Moeaha & M.T. Nembudani (2015). Identification guide to the southern African grasses. An identification manual with keys, descriptions and distributions. Strelitzia 36. Google Scholar

    18.

    Hackel, J., M.S. Vorontsova, O.P. Nanjarisoa, R.C. Hall, J. Razanatsoa, P. Malakasi & G. Besnard (2018). Grass diversification in Madagascar: In situ radiation of two large C3 shade clades and support for a Miocene to Pliocene origin of C4 grassy biomes. J. Biogeogr. 45: 750–761. Google Scholar

    19.

    Henrard, J.T. (1950). Monograph of the genus Digitaria. Universitaire Pers, Leiden. Google Scholar

    20.

    Hitchcock, A.S. & A. Chase (1910). The North American species of Panicum. Contr. U. S. Natl. Herb. 15. Google Scholar

    21.

    Hodkinson, T.R. (2018). Evolution and taxonomy of the grasses (Poaceae): a model family for the study of species-rich groups. Ann. Plant Rev. 1: 1–39.  https://doi.org/10.1002/9781119312994.apr0622 Google Scholar

    22.

    Hubbard, C.E. & R.E. Vaughan (1940). The grasses of Mauritius and Rodriguez. Director of Agriculture, Port-Louis and Crown Agents for the Colonies, London. Google Scholar

    23.

    Hutchinson, J. & J.M. Dalziel (1972). Juncaceae, Gramineae. In : Hepper, F.N. (ed.), Fl. W. Trop. Africa 3(2). Ed. 2. Crown Agents for the Colonies, London. Google Scholar

    24.

    Jarvis, C. (2007). Order out of chaos. Linnaean plant names and their types . The Linnaean Society of London and Natural History Museum, London. Google Scholar

    25.

    Kellogg, E.A. (2015). Poaceae. In : K. Kubitzki (ed.), The families and genera of vascular plants 13. Springer. Google Scholar

    26.

    Morrone, O. & F.O. Zuloaga (1992). Revisión de las especies sudamericanas nativas e introducidas de los géneros Brachiaria y Urochloa (Poaceae: Panicoideae: Paniceae). Darwiniana 31: 43–109. Google Scholar

    27.

    Morrone, O. & F.O. Zuloaga (1993). A synopsis of the genus Urochloa (Poaceae: Panicoideae: Panicea) from Mexico and Central America. Darwiniana 32: 59–75. Google Scholar

    28.

    Nees von Esenbeck, C.G.D. (1829). Flora Brasiliensis seu Enumeratio Plantarum in Brasilia. Vol. 2. Stuttgart & Tübingen, Germany. Google Scholar

    29.

    Perrier de la Bâthie, H. (1931) Les plantes introduites à Madagascar. Rev. Bot. Appl. Agric. Trop. 11: 719–729, 833–837, 920–932, 990–999. Google Scholar

    30.

    Perrier de la Bâthie, H. (1932) Les plantes introduites à Madagascar. Rev. Bot. Appl. Agric. Trop. 12: 48–52, 128–133, 213–220, 296–301, 372–383, 462–468, 530–543. Google Scholar

    31.

    Robyns, W. (1932). Contribution a l'étude des Graminées du Congo Belge et du Ruanda-Urundi. II. Panicées. Bull. Jard. Bot. État Bruxelles 9: 171–202. Google Scholar

    32.

    Soreng, R.J., P.M. Peterson, K. Romaschenko, G. Davidse, J.K. Teisher, L.G. Clark, P. Barberá, L.J. Gillespie & F.O. Zuloaga (2017). A worldwide phylogenetic classification of the Poaceae (Gramineae) II: An update and a comparison of two 2015 classifications. J. Syst. Evol. 55: 259–290. Google Scholar

    33.

    Sosef, M.S.M. (2016). Taxonomic novelties in central African grasses (Poaceae), Paniceae 1. Plant Ecol. Evol. 149: 356–365. Google Scholar

    34.

    Stapf, O. (1919). 1638. Panicum epacridifolium. Bull. Misc. Inform. Kew 1919: 266–267. Google Scholar

    35.

    Steudel, E.G. (1854). Synopsis Plantarum Glumacearum 1(6). J.B. Metzler, Stuttgart. Google Scholar

    36.

    Torres González, A.M. & C.M. Morton (2005). Molecular and morphological phylogenetic analysis of Brachiaria and Urochloa (Poaceae). Mol. Phyl. Evol. 37: 36–44. Google Scholar

    37.

    Veldkamp, J.F. (1996). Brachiaria, Urochloa (Gramineae-Paniceae) in Malesia. Blumea 41: 413–437. Google Scholar

    38.

    Veldkamp, J.F. (2004). Miscellaneous notes on mainly Southeast Asian Gramineae. Reinwardtia 12: 135–140. Google Scholar

    39.

    Vorontsova, M.S., G. Besnard, F. Forest, P. Malakasi, J. Moat, W.D. Clayton, S.Z. Ficinski, G.M. Savva, O.P. Nanjarisoa, J. Razanatsoa, F.O. Randriatsara, J.M. Kimeu, W.R.Q. Luke, C. Kayombo & H.P. Linder (2016). Madagascar's grasses and grasslands: anthropogenic or natural? Proc. Roy. Soc. Biol. Sci. Ser. B. 283: 2015–2262. Google Scholar

    40.

    Vorontsova, M.S. (2018). Revision of the group previously known as Panicum (Poaceae) in Madagascar, including Adenochloa, Trichanthecium, and Urochloa maxima. Candollea 73: 143–186. Google Scholar

    41.

    Zuloaga, F.O., D.L. Salariato & A. Scataglini. (2018). Molecular phylogeny of Panicum s. str. (Poaceae, Panicoideae, Paniceae) and insights into its biogeography and evolution. PloS one 13: p.e0191529. Google Scholar

    Appendices

    Appendix

    Placements of the 31 accepted species from chloroplast phylogenetic reconstruction by Hackel et al. (2018) except those inferred from morphology [*].

    img-z38-2_199.gif
    © CONSERVATOIRE ET JARDIN BOTANIQUES DE GENÈVE 2022
    Maria S. Vorontsova "Revision of some Malagasy forage grasses and their relatives within Brachiaria, Echinochloa, Moorochloa, and Urochloa," Candollea 77(2), 199-236, (15 November 2022). https://doi.org/10.15553/c2022v772a7
    Received: 9 May 2022; Accepted: 4 October 2022; Published: 15 November 2022
    KEYWORDS
    Brachiaria
    Echinochloa
    Madagascar
    Moorochloa
    new combinations
    Panicoideae
    Poaceae
    Back to Top