Introduction

The first comprehensive taxonomic revision of the Neotropical genus Werneria Kunth (Compositae, Senecioneae) was published in 1939 by German biologist E. F. M. Rockhausen, carried out within the frame of his dissertation under the supervision of F. L. E. Diels and R. K. F. Pilger (Rockhausen 1939). Rockhausen recognized 37 species; however, the circumscription of the genus was significantly narrowed after segregating several species that were placed within the new genera Xenophyllum V. A. Funk and Misbrookea V. A. Funk (see Funk 1997a, 1997b).

Following this criterion, the genus Werneria embraces rosettiform or scapiform perennial herbs, without genuine stems. These species display involucral bracts usually fused at the base (strongly partite in a few species), capitula radiate or discoid (disciform in one species), ray florets white or yellow when present, filament collar balusterform, and style branches truncate with a crown of sweeping hairs. Although two species bear supplementary bracts at the base of the involucre, their absence should be considered as another characteristic feature of the genus. They are mainly distributed through the Andean highlands from southern Argentina and Chile to western Venezuela. Only one species, W. nubigena Kunth, occurs also in Central America northward to Tacaná Volcano in southern Chiapas (Mexico). Recent studies estimate the number of Werneria species at 27 (Calvo unpublished data).

The present work is part of ongoing studies on the genus Werneria (e.g. Beltrán 2017; Beltrán & Leiva 2018; Calvo & Beltrán 2019; Calvo & Meneses 2019; Calvo & Moreira-Muñoz 2019). Herein, we present a clarification of the taxonomic entity W. weberbaueriana and describe two new species on the basis of morphological evidence. These are known only from central Peru, two of them putative endemics of the Cordillera Blanca in Ancash Department (Fig. 3). A key to the Werneria species occurring in this department is also provided.

Material and methods

This contribution is the result of an intensive review of the published bibliography, field work in Peru, and the revision of herbarium specimens kept at F, LPB, MO, QCNE, US, and USM; herbarium codes follow Thiers (2019+).

Results and Discussion

1. Werneria weberbaueriana Rockh.

Type: Peru, Ancash, [“Cordillera Blanca bei Huaraz, 4300–4500 m a.s.l., May 1903, A. Weberbauer 2984” according to the ind. loc.] (B, destroyed). – Neotype (designated here): Peru, Ancash, Huari [Asunción], Huascarán N.P., just crossing the Ulta pass, 4870 m a.s.l., 09°07'S, 77°30'W, 28 Jul 1985, D. N. Smith 11303 ( US barcode US-00622845; isoneotypes: F accession no. 1960115, MO accession no. 3316165, USM accession no. 69993). – Fig. 1, 2B.

Description — Rhizomatous herb, rosettiform, forming mats, 2–2.5 cm tall. Rhizome 4–7 cm long, 0.3–0.6 cm in diam., horizontal to oblique, glabrous. Leaves simple, alternate, pseudopetiolate; leaf lamina spatulate to flabellate, 2–2.5 mm long, 2.5–3.5 mm wide, entire, truncate, thickened, 5–7-notched at apex, attenuate to cuneate at base, strongly conduplicate upward in cross-section, glabrous, 1-nerved above (barely conspicuous), 1-nerved beneath, fleshy, matte, papillose-verrucose near apex; pseudopetiole 6.5–7.5 mm long, with scattered short marginal trichomes 0.05–0.1 mm long. Capitulum radiate, solitary, terminal, sessile to subsessile. Involucre 10–12 mm long, 7–8 mm wide, cupuliform, with bracts fused at base, glabrous; involucral bracts c. 11, c. 5 mm long, c. 2 mm wide at base, obtuse at apex, purplish; supplementary bracts absent. Ray florets 11–12, 7–8.1 mm long, c. 1 mm wide, 3-veined, subentire to 3-toothed at apex, not surpassing involucre, white. Disc florets c. 29, 5–5.5 mm long, 5-lobed, white with lobes purple-tipped; style branches truncate with a crown of sweeping-hairs, white. Achenes 2.7–2.8 mm long, 0.6–0.8 mm wide, cylindric, 7- or 8-ribbed, glabrous, papillose; pappus 3.5–6.6 mm long, barbellate, whitish. Chromosome number unknown.

Fig. 1.

Werneria weberbaueriana – A: habit; B: detail of leaves and capitulum. – Peru, Ancash, Asunción, surroundings of laguna Lebrón, 20 May 2009, photographed by A. Cano.

Phenology — Collected in flower from May to July.

Distribution and ecology — Endemic to Peru (Ancash). Known only from the central part of the Cordillera Blanca (Fig. 3B). The species grows on exposed rocky slopes and cryoturbated soils around the upper limit of vegetation, at elevations of 4400–4870 m a.s.l. Some species observed in the same habitat are: Draba depressa Hook. f. (Cruciferae), Gentianella weberbaueri (Gilg) Fabris (Gentianaceae), and Nototriche coccinea A. W. Hill. (Malvaceae).

Etymology — The specific epithet honours the German botanist A. Weberbauer (1871–1948), who devoted part of his life to the study of the Peruvian flora.

Fig. 2.

A: Werneria rockhauseniana; A1: leaf apex; A2: leaf apex lower surface (flattened); drawn from Smith & Valencia 9950. – B: W. weberbaueriana; B1: leaf apex; B2: leaf apex lower surface (flattened); drawn from Smith 11303. – Drawings by J. Calvo.

Conservation status — The category Data Deficient (DD) is assigned because data are inadequate to determine a threat category (IUCN 2012). Further collections are needed in order to firmly assess its conservation status.

Remarks — Little is known about Rockhausen except that, as he stated himself (Rockhausen 1939), he received some guidance from A. Weberbauer (1871–1948), an outstanding German botanist who greatly contributed to the knowledge of the Peruvian flora. In recognition for this help, Rockhausen named a new species from Peru in his hon-our, i.e. Werneria weberbaueriana.

As stated in the protologue, this species was described based on one collection from the Cordillera Blanca in Ancash previously misidentified as Werneria aretioides Wedd., a species distributed in southern Peru, western Bolivia, northern Chile, and northwestern Argentina. Rockhausen (1939) separated the new species from W. aretioides by the absence of a denticulate leaf margin, the leaf lamina being distally papillose-verrucose, and the style branches not being purple coloured.

Since the publication of Werneria weberbaueriana in 1939, few botanists focused their interest on this species. Recently, in the framework of a synopsis of the Peruvian Werneria species, Beltrán (2017) highlighted the papillose-verrucose leaves and yellow ray florets as diagnostic characters of this species. The striking inconsistency on the ray floret colour, which was originally described as white, led to our interest to this matter. After studying the Werneria material kept at USM, we realized that two distinct taxonomic entities were interchangeably identified as W. weberbaueriana. Indeed, an important character to discriminate one from the other is the colour of the ray florets but significant differences were also found in the leaf morphology (discussed below). Although the type material of W. weberbaueriana was apparently destroyed at B in 1943, the detailed description provided in the protologue clearly corresponds to the species displaying white ray florets and a notched leaf apex. In order to remove any uncertainty surrounding the application of this name, we consider it appropriate to designate a neotype. The selected specimen is a collection by D. N. Smith from a locality not far from the type locality indicated in the protologue. It is a suitable collection because the label explicitly indicates that the ray florets are white. On the other hand, the taxonomic entity with yellow ray florets is described as a new species (see below).

Additional specimen examined — Peru: Ancash, Asunción, Chacas, alrededores de laguna Lebrón, 09°12'S, 77°29'W, 20 May 2009, A. Cano & al. 19373 (USM accession no. 299010).

2. Werneria rockhauseniana H. Beltrán, Trinidad & J. Calvo, sp. nov. – Fig. 2A, 4.

Holotype: Peru, Ancash, Huaylas, Huascarán N.P.,

pass between quebrada Los Cedros and Hatuncocha, 08°51'S, 77°45'W, 4600–4850 m a.s.l., 12 Mar 1985, D. N. Smith & R. Valencia 9950 (USM accession no. 68139; isotypes: F accession no. 1962951, LPB s.n., MO accession no. 3316189, QCNE accession no. 58168, US barcode US-00622663).

Diagnosis — The new species differs from Werneria weberbaueriana by having the leaf lamina plainly entire at the apex, the ray florets, disc florets, and style branches yellow, and the pseudopetioles glabrous.

Description — Rhizomatous herb, rosettiform, forming mats, 2–2.5 cm tall. Rhizome 3–6 cm long, 0.2–0.3 cm in diam., horizontal to oblique, glabrous. Leaves simple, alternate, pseudopetiolate; leaf lamina spatulate, 2.4–2.6 mm long, 2.2–2.5 mm wide, entire, truncate, thickened at apex, attenuate to cuneate at base, strongly conduplicate upward in cross-section (sometimes nearly tubular when young), glabrous, 1-nerved above (barely conspicuous), 1-nerved beneath, fleshy, matte, papillose near apex (rarely without papillae); pseudopetiole 4.8–12.1 mm long, glabrous. Capitulum radiate, solitary, terminal, sessile to subsessile. Involucre 7.4–8.2 mm long, 5.7–6.5 mm wide, cupuliform, with bracts fused at base, glabrous; involucral bracts 11–13, 3.6–4.8 mm long, 1.6–1.7 mm wide at base, obtuse at apex, greenish to purplish; supplementary bracts absent. Ray florets 11–20, 5.5–5.6 mm long, 0.6–1 mm wide, 3- or 4-veined, subentire to 3-toothed at apex, not surpassing involucre, yellow. Disc florets 32–33, 4.6–4.9 mm long, 5-lobed, yellow; style branches truncate with a crown of sweeping-hairs, yellow. Achenes 2.4–2.7 mm long, 0.6–0.7 mm wide, cylindric, 6- or 9-ribbed, glabrous, papillose; pappus 3.5–4.5 mm long, barbellate, whitish. Chromosome number unknown.

Fig. 3.

A: Peru and adjacent countries; rectangle showing area of distribution maps B–D; B: Werneria weberbaueriana (△); C: W. rockhauseniana (○); D: W. huascarana (×).

Phenology — Flowering nearly all year round.

Distribution and ecology — Endemic to Peru (Ancash, Huánuco [expected], Lima). It is distributed through the Cordillera Blanca and Cordillera Huayhuash (Fig. 3C). The species grows on exposed rocky slopes around the upper limit of vegetation, at elevations of 4200–6040 m a.s.l. In the same habitat the following species were observed: Azorella pulvinata Wedd. (Umbelliferae), Bomarea dulcis (Hook.) Beauverd (Alstroemeriaceae), Chersodoma ovopedata (Cuatrec.) Cuatrec., Chuquiraga spinosa Less., Senecio burkartii Cabrera, Senecio canes-cens (Bonpl.) Cuatrec., Senecio collinus DC., Senecio culcitioides Sch. Bip., Werneria orbignyana Wedd., and Xenophyllum dactylophyllum (Sch. Bip.) V.A. Funk. (all Compositae).

Etymology — The specific epithet honours the German biologist E. F. M. Rockhausen (1911–?), who published the first comprehensive revision of the Neotropical genus Werneria.

Conservation status — Based on the information available to us, this species does not meet the criteria to be considered as Vulnerable (VUL) because the number of known locations is more than ten (collections and observations) and most populations grow in protected areas, i.e. Huascarán National Park and Cordillera Huayhuash Reserved Zone. Consequently, Werneria rockhauseniana is preliminarily assigned to the category Near Threatened (NT) according to IUCN Red List categories and criteria (IUCN 2012).

Fig. 4.

Werneria rockhauseniana – A: habit; B: leaves; C: capitulum. – Peru, Lima, Cajatambo, 16 Oct 2017, photographed by H. Trinidad.

Remarks — Werneria rockhauseniana has been confused with W. weberbaueriana (Beltrán 2017), with which it partially overlaps in distribution area. They can be differentiated by the colour of the ray florets (yellow in W. rockhauseniana [Fig. 4C] vs. white in W. weberbaueriana [Fig. 1B]), colour of the disc florets (yellow in W. rockhauseniana vs. white with lobes purple-tipped in W. weberbaueriana [Fig. as above]), colour of the style branches (yellow in W. rockhauseniana vs. white in W. weberbaueriana [Fig. as above]), and leaf lamina apex (plainly entire in W. rockhauseniana [Fig. 2A, 4B] vs. 5–7-notched in W. weberbaueriana [Fig. 1B, 2B]. Moreover, W. rockhauseniana has glabrous pseudopetioles, whereas in W. weberbaueriana they bear short, scattered, marginal trichomes.

Additional specimens examined — Peru: Ancash, Bolognesi, Pacllón, sector Jahuacocha, Cordillera Huayhuash, cumbre del Nevado Rasác, 10°16'S, 76°55'W, 15 Jun 2004, C. Callupe s.n. (USM accession no. 235163); Huaylas, 19 May 2000, A. Cano & al. 10475 (USM accession no. 161429); Asunción, Chacas, alrededores de la laguna Lebrón, 09°12'S, 77°29'W, 20 May 2009, A. Cano & al. 19372 (USM accession no. 299009); near top of divide over Cordillera Blanca, upper slopes of Huascarán, above lagunas Llanganuco, 09°01'S, 77°35'W, 10 Jul 1982, A. Gentry & al. 37441 (MO accession no. 3100003, USM accession no. 57498); Recuay, Huascarán N.P., mouth of quebrada Quenua Ragua, 09°58'S, 77°13'W, 10 May 1985, D. N. Smith, R. Valencia & A. Gonzales 10655 (MO accession no. 3316191, USM accession no. 69032); Carhuaz, Huascarán N.P., quebrada Ishinca, side valley to laguna Ishinca, 09°23'S, 77°25'W, 16 Jul 1985, D. N. Smith & M. Buddensiek 11213 (F accession no. 1960571, MO accession no. 3316192, USM accession no. 166000); Carhuaz, Huascarán N.P., quebrada Ulta, near Ulta pass, 09°07'S, 77°30'W, 28 Jul 1985, D. N. Smith 11309 (F accession no. 1960118, MO accession no. 3316190, USM accession no. 69999); Yungay, Huascarán N.P., Llanganuco sector, quebrada Ancosh at portachuelo, 09°03'S, 77°35'W, 31 Dec 1984, D. N. Smith & K. Goodwin 8893 (F accession no. 1962952, MO accession no. 3316188, USM accession no. 66982). Lima, Cajatambo, Raura, 10°26'S, 76°47'W, 15 Apr 1988, S. Rivas & al. s.n. (USM accession no. 165997).

3. Werneria huascarana J. Calvo, H. Beltrán & Trinidad, sp. nov. – Fig. 5.

Holotype: Peru, Ancash, Carhuaz, Huascarán National Park, quebrada Ulta, near Ulta pass, 09°07'S, 77°30'W, 4870 m a.s.l., 28 Jul 1985, D. N. Smith 11308 (USM accession no. 69998; isotype: MO n.v.).

Diagnosis — Werneria huascarana differs from the other species of the genus by the combination of the following characters: rhizomes covered by long silky trichomes and leaf-base remnants, leaf lamina narrowly elliptic, glabrous, 6.5–12 mm long, supplementary bracts absent, ray florets yellow.

Description — Rhizomatous herb, rosettiform, forming lax clumps, 2–3 cm tall. Rhizome 6–8 cm long, 0.2–0.3 cm in diam., horizontal to oblique, covered by long silky trichomes and leaf-base remnants. Leaves simple, alternate, prolonged into a sheath-like base bearing long silky trichomes; leaf lamina narrowly elliptic, 6.5–12 mm long, 1.5–2.5 mm wide, entire, acute, callous-tipped at apex, attenuate at base, flat in cross-section, glabrous, 1-nerved above (barely conspicuous), 1-nerved beneath (barely conspicuous), somewhat fleshy, matte. Capitulum radiate, solitary, terminal, sessile to subsessile. Involucre 10–11 mm long, 7–8 mm wide, cupuliform, with bracts fused at base, glabrous; involucral bracts c. 13, 4–4.5 mm long, 1.5–2 mm wide at base, acute at apex, greenish; supplementary bracts absent. Ray florets c. 10, 10–11 mm long, 1.8–2.1 mm wide, 4- or 5-veined, 3-toothed at apex, conspicuously surpassing involucre, yellow. Disc florets c. 60, 6–6.5 mm long, 5-lobed, yellow; style branches truncate with a crown of sweeping-hairs, yellow. Achenes cylindric, glabrous (immature); pappus c. 5 mm long, barbellate, whitish. Chromosome number unknown.

Phenology — Collected in flower from April to July (also seen in flower in November).

Distribution and ecology — Endemic to Peru (Ancash). Until now, Werneria huascarana is known only from the surroundings of the Ulta pass, located between the cities of Carhuaz and Chacas in the central part of the Cordillera Blanca (Fig. 3D). The species grows on rock outcrops and scree slopes around the upper limit of vegeta- tion, at elevations of 4700–4900 m a.s.l. It occurs along with Brayopsis calycina (Desv.) Gilg & Muschl. (Cruciferae), Chersodoma ovopedata, Lachemilla tanacetifolia Rothm. (Rosaceae), Senecio comosus Sch. Bip., Senecio scrobicarioides DC. (both Compositae), Urtica echinata Benth. (Urticaceae), and Xenophyllum dactylophyllum.

Etymology — The specific epithet refers to the Huascarán National Park, from where this species is known.

Conservation status — Data are inadequate to determine a threat category, and therefore the category Data Deficient (DD) is assigned (IUCN 2012).

Remarks — Among the species displaying yellow ray florets, Werneria huascarana may be confused with W. canaliculata Sch. Bip., W. cornea S.F. Blake, and W. pumila Kunth. The leaf characters are useful to discriminate it from W. canaliculata, i.e. shape (narrowly elliptic vs. linear in W. canaliculata), length (6.5–12 mm long vs. 8–37 mm long in W. canaliculata), venation of the lower surface (midrib barely conspicuous vs. midrib remarkably prominent and usually canaliculate in W. canaliculata), and texture (somewhat fleshy vs. rather coriaceous in W. canaliculata). The distribution area of W. canaliculata ranges from Huancavelica (Peru) to La Paz (Bolivia), and therefore the distribution areas of this and W. huascarana do not overlap. Werneria huascarana can be readily differentiated from W. cornea by the leaf shape (narrowly elliptic vs. linear, somewhat falcate in W. cornea) and leaf apex (acute, callous-tipped vs. obtuse in W. cornea). Moreover, W. cornea has rather coriaceous leaves with a remarkably thickened margin. Both species occur in Ancash Department. Werneria huascarana differs from W. pumila in the leaf shape and length (narrowly elliptic, 6.5–12 mm long vs. linear-oblanceolate, 18–85 mm long in W. pumila), number of involucral bracts (c. 13 vs. 19–21 in W. pumila), and absence of supplementary bracts (12–16 in W. pumila). Their distribution areas do not overlap.

Fig. 5.

Werneria huascarana. – A: habit; B: detail of leaves and capitulum. – Peru, Ancash, Asunción, abra de punta Olímpica, 15 Nov 2006, photographed by A. Cano.

The habit and leaves of Werneria huascarana also show some morphological similarities to those of W. pygmaea Gillies ex Hook. & Arn., especially in Ancash Department, where this species displays narrowly oblanceolate leaves wider than typical forms. However, any confusion is unlikely because W. pygmaea has white ray florets.

Additional specimen examined — Peru: Ancash, Asunción, Chacas, abra de punta Olímpica, 09°07'S, 77°30'W, 24 Apr 2004, A. Cano, M. I. La Torre & W. Mendoza 14507 (USM accession no. 210736).