Aloysia Paláu, Parte Prac. Bot. 1: 767. 1784.

Type: Aloysia citrodora Paláu

Verbena L. sect. Aloysioides Walp., Rep. Sp. Nov. 4: 13. 1845.

Lippia L. sect. Aloysia Schau. in dc., Prodr. 11: 572. 1847.

Lippia L. subgen. Aloysia Schau. in Engler and Prantl, Die Naturlich. Pflanzenfam. 4(3A): 151. 1897.

Zapania Lam., Tabl. Encycl. 1: 59. 1791, nom. illeg.

Perennial, phanerophytic sub-shrubs, shrubs or trees, narrowly upright to ascending, 0.5–15.0 m high. Stems 4-angled in cross section becoming multi-angular to rounded with age; pubescent, glabrate with age, surface smooth, becoming furrowed or longitudinally multi-striated. Leaves evergreen or dry-season deciduous, simple, exstipulate, mostly opposite or 3(-4)-whorled, occasionally alternate or clustered into fascicles; Laminae linear, elliptic, lanceolate, spathulate, obovate, ovate, orbicular to cordate, basally attenuate to cordate, apically retuse to acuminate; margins entire, crenate, crenulate, crenate-serrate, dentate, to serrate; adaxially glabrous or scabrous, hispidulous, to strigulose; abaxially strigulose to incanous, often with sub-sessile, single-celled glandular trichomes. Inflorescences spicate racemes, occasionally paniculate; flowers often in clusters of 3–6 with elongated internodes intervening; rachis rounded to tetragonal, adpressed-villous to incanous, occasionally bearing long-stalked, glandular trichomes; often elongating through anthesis and maturation of fruit. Flowers sessile to pedicellate, pedicels 0.5 to 3 mm long, subtended by foliaceous bracts. Bracts inferior to flowers, linear, lanceolate, elliptic, to ovate; abaxially strigulose to setose; apically acute to acuminate. Calyces 2 or 4 lobed, sub-actinomorphic to zygomorphic, externally strigulose, setose, or velutinous, often sub-sessile glandular, internally glabrous; fully accrescent in fruit and persistently enclosing mature schizocarp. Corollas sub-actinomorphic to zygomorphic, salverform to infundibuliform, white, lavender, purple, pink, or blue; tube cylindrical to gibbous, glabrous to variously pubescent externally, internally villous along distal half; limb 4-lobed, superior lobe often cleft, glabrous to villulous; externally glabrous to strigulose. Styles filiform and usually glabrous, occasionally villous along base. Stigmas capitate to sub-capitate, bilobed; lobes approximately equal or oblique, apically or laterally disposed. Stamens 4, epipetalous, sub-equal to didynamous, superior pair sometimes weakly exserted; theca longitudinally dehiscent, 0.15–0.50 mm long. Fruits composed of two schizocarps, ellipsoid to obovoid, often more or less cordate, basally truncate, apically rounded to bilobed, glabrous or setose; mericarps two, readily dehiscent at maturity; intermericarpal cavity present or absent, the surface smooth to papillate. Base chromosome number is 9 (Powell et al. 2010).

Iconography: Paláu (1784, un-numbered illustration by B. Salvador y Carmona [lectotype of Aloysia citrodora Paláu]).

Aloysia is an amphitropical genus of 30 species native to arid, temperate and subtropical regions of North and South America. It can be found at elevations ranging from near sea level up to approximately 4000 meters in the Andes Mountains of South America. Members of this genus are widely cultivated for culinary, medicinal, and ornamental purposes.

Type: perú. Arequipa: Mpio. Arequipa; Tiabaya; open, rocky slope, 8 Apr 1925, F. W. Pennell 13079 (HOLOTYPE: NY!; isotypes: F!, GH!, S!).

Aloysia scorodonioides similis; frutex sub 0.5 m; ramulis gracilibus, quadrangulatis vel rotundatis; petiolis 1.0–2.0 mm longis; laminis anguste elliptiis, 1.0–1.5 cm longis, basim cuneatis, marginibus crenato-serratis; inflorescentiis racemis spiciformibus cylindricis congestis, 2.0–4.0 cm longis; pedunculis ca. 1 cm longis; calycibus quadrilobus campanulatis.

Similar to Aloysia scorodonioides; shrub under 0.5 m; stems gracile, four-angled to rounded; petioles 1.0–2.0 mm long; laminae narrowly elliptic, 1.0–1.5 cm long, base cuneate, margins crenate-serrate; inflorescence a spicate raceme, cylindrical, congested, 2.0–4.0 cm long; peduncle ca. 1 cm long; calyx four-lobed, campanulate.

Shrubs 0.5–1.5 m in height. leaves opposite, rarely 3-whorled; petioles 1–2 mm long; laminae 1–2 cm long, 0.5–1.2 cm wide, elliptic, margins finely serrate along apical 2/3 to 1/2, basally entire, adaxially strigose, abaxially tomentose, with an understory of sub-sessile, glandular trichomes. inflorescence more or less loosely spicate, mostly terminal; peduncle 0.5–2.0 cm long, densely strigulose with an understory of subsessile, glandular trichomes; rachis 1.5–5.0 cm long, densely strigulose with an understory of sub-sessile, glandular trichomes. BRACTS reduced, lance-elliptic, 1–3mmlong, 0.5–1.0mmlong, apically acute to short-acuminate, strigulose, with an understory of sub-sessile, glandular trichomes. calyx sub-actinomorphic, campanulate, setulose to setose, with an understory of sub-sessile, glandular trichomes; lobes 4, triangular. corolla weakly zygomorphic, lavender to pink, often with a whitish limb; tube 2–3 mm long, pubescent with an understory of sub-sessile, glandular trichomes present distally; limb 3–4 mm wide. stigma sub-capitate, apically disposed, lobes obscure. fruit obovoid, 1.0–1.5 mm long, 1.0–1.5 mm wide, glabrous, apically bilobed, lobes 0.2–0.5 mm; intermericarpal cavity reduced, surface papillate.

Additional Specimens Examined: perú. Arequipa: Mpio. Arequipa; 12 km S of Arequipa, in rocky gulch, 14 Sep 1938, W. J. Eyerdam & A. A. Beetle 22129 (GH, UC); encima de los Baños de Jesú s, ladera rocosa, 2600–2700 m, 23 Apr 1961, R. Ferreyra 14253 (MO); Tingo, open, rocky slope, 8 Apr 1925, F. W. Pennell 13134 (F, NY, S, US); Arequipa, slopes of Pichu Pichu, Feb 1943, 9500 ft [2895.5 m], C. Sandeman 3835 (F); Arequipa, lower slope of El Misti in volcanic ash, 22 Mar 1951, S. Saunders 102 (TEX); Cerros de Jesú s, 10 Apr 1959, C. Vargas C. 12671 (US); Quequena, arenoso, 17 Mar 1967, C. Vargas C. 19146 (LL). Mpio. Castilla; Quebrada de San Lorenzo, near Arequipa, rockywall, 11Mar 1939, P. A. Munz 15509 (NY-2). Lima:Mpio. Yauyos; Aiza, entre Catahuas y Tupe, Pradera, 30 Jan 1952, E. Cerrate 1282 & O. Tovar 696 (MO, SI).

Aloysia arequipensis is morphologically similar to A. scorodonioides (Kunth) Moldenke from which it is readily distinguished by inflorescence, flower and leaf morphology; the former has inflorescences with somewhat congested flowers, corolla tubes that are two to four times the length of the calyx, and elliptic leaves which are basally entire and finely serrate along the distal two-thirds, the latter has inflorescences with somewhat congested to loosely arranged flowers, corolla tubes that are less than two times the length of the calyx, and ovate to orbicular leaves with crenate to crenate-dentate margins. Aloysia arequipensis is native to arid climates in the states of Arequipa and Lima, Peru at elevations of 2000–3000 m. It flowers from spring to fall and reportedly has a ‘‘thymelike scent'' (Sandeman 3835).

Type: méxico. Michoacán: Mpio. Coalcoman de Matamoros; Sierra Naranjillo, Coalcoman, 1550 m, woods, frequent, 11 Mar 1941, Hinton et al. 15766 (holotype: LL!; isotypes: G!, MICH!, NY!, S!, UC!, W!).

Aloysia nahuire similis; frutex sub six metralis; ramulis gracilibus, quadrangulatis vel rotundatis; petiolis 0.6–1.0 cm longis; laminis anguste lanceolatis elliptiis 6–10 cm longis, 2–3 cm latis, basim rotundus, marginibus serratis; inflorescentiis racemis spiciformibus congestis, pedunculis 1–5 cm longis, rachidibus 1.5–4.0 cm longis; pedicelis 2–3 mm longis; bracteolis conspicuis anguste elliptiis vel elliptiis, 4–6 mm longis, 1.5–2.0 mm latis; calycibus bilobis.

Similar to Aloysia nahuire; shrub under six meters; stems gracile, four-angled to rounded; petioles 0.6–1.0 cm long; laminae narrowly lanceolate-elliptic, 6–10 cm long, 2–3 cm wide, base rounded, margins serrate; inflorescence a spicate raceme, congested, peduncles 1–5 cm long, rachis 1.5–4.0 cm long; pedicels 2–3 mm long; bracts conspicuous, narrowly elliptic to elliptic, 4–6 mm long, 1.5–2.0 mm wide; calyx bilobed.

Shrub to small tree up to 6 m in height. Leaves opposite; petioles 0.6–1.0 cm long; laminae 6–10 cm long, 2–3 cm wide, narrowly lance-elliptic, margins finely serrate, revolute, adaxially scabrous, abaxially sparsely villous, with an understory of sub-sessile, glandular trichomes. Inflorescence compactly spicate; peduncle 1–5 cm long, antrorsely strigulose mixed with longstalked, glandular trichomes; rachis 1.5–4.0 cm long, antrorsely strigulose mixed with long-stalked, glandular trichomes; pedicels 2–3 mm long. BRACTS foliaceous, narrowly elliptic to elliptic, 4–6 mm long, 1.5–2.0 mm wide, apically acuminate, tip usually revolute, strigulose. Calyx bilobed, 1.5–2.5 mm long, externally setose, glandular, lobes apically rounded, margins ciliate. Corolla zygomorphic; tube 2.0–2.5 mm long, strigulose distally; limb 2–3 mm wide, lateral lobes glabrous, superior and inferior lobes strigulose. Stigma subcapitate, laterally disposed. FRUIT obovoid, 1.5–2.0 mm long, 1.5–2.0 mm wide, glabrous, apically bilobed, lobes 0.1–0.2 mm long; intermericarpal cavity enlarged, the surface papillate.

Aloysia coalcomana is known from a single collection in the mountains known as the Sierra Naranjillo in the Municipio of Coalcoman de Matamoros, Michoacán, México. It is morphologically similar to A. nahuire Moldenke from which it is readily distinguished by its habitat, habit, pedicels, and floral bracts; the latter is a shrub of low elevation, coastal thorn forests 1–4 m tall with pedicels 0.5 to 1.0 mm long and ovate bracts 8–10 mm long. Aloysia coalcomana is a shrub or small tree of high elevation, montane woodlands up to 6 m tall with pedicels 2–3 mm long and elliptic bracts 4–6 mm long. The novelty appears to flower in the spring and was reportedly common in the area at the time of collection (Hinton et al. 15766). The area of the type locality was visited on March 16, 1999. Unfortunately, much of the area in the mountains had been cleared and little undisturbed vegetation remained. The area along the highway between Coalcoman de Matamoros and Villa Victoria was surveyed for several hours, but neither the woodland described on the original collection label nor any specimens of Aloysia were encountered.

Type: brazil. Paraná : Mpio. São José dos Pinhaes; Río Pequeno, do brejo, 17 Jan 1969, G. Hatschbach 20792 (holotype: NY!; isotypes: K!, MICH!, MO!, UC!).

Aloysia brasiliensis similis; frutex 1–2 m; ramulis glabris, gracilibus; foliis ternatis et sessilibus; laminis cordatis, glabris; marginibus minutae-scabrosis, basim cordatis, apicem subapiculatis; inflorescentiis racemis spiciformibus laxis; corollis lilacinus.

Similar to Aloysia brasiliensis; shrub 1–2 m; stems glabrous, gracile; leaves ternate and sessile; laminae cordate, glabrous; margins minutely scabrous, base cordate, apex sub-apiculate; inflorescence a spicate raceme, lax; corolla lilac.

Shrub 1–2 m in height, slender, fewbranched. LEAVES 3-whorled, antrorsely adpressed, internodes highly regular in length, sessile; laminae cordate, sclerophyllous, 0.3–1.0 cm long, 0.3–0.9 cm wide, margins entire, minutely scabrous, basally cordate, apically mucronulate, adaxially glabrous, smooth, lustrous, abaxially glabrous, smooth, satin-lustrous. Inflorescence loosely spicate; peduncle 1–3 cm long, strigulose; rachis 4–12 cm long, strigulose; pedicels 0.5–1.0 mm long. Bracts reduced, linear to lanceolate, 1.0–1.5 mm long, ca. 0.5 mm wide, acuminate, strigulose. Calyx zygomorphic, tubular; 1.5–2.0 mm long, setose, glandular, lobes 4, trullate, acute. Corolla sub-actinomorphic, lilac; tube 2.5–3.5 mm long, sparsely villulous apically; limb 2–3 mm wide. Stigma capitate, apically disposed, lobes oblique. Fruit obovoid, 1.0–1.5 mm long, 1.0–1.5 mm wide, glabrous, apically weakly bilobed, lobes less than 0.1 mm; intermericarpal cavity reduced, surface smooth.

Additional specimens examined: BRAZIL. Paraná : Mpio. Piraquara; Novo Tirol, local brejoso, raro, 27 Nov 1964, G. Hatschbach 11896 (F, MBM); S. Maria, 11 Oct 1969, G. Hatschbach 22418 (UC). Mpio. Quatro Barras; Quatro Barras, 22 Apr 1961, G. Hatschbach 8437 (LL). Mpio. São José dos Pinhais; Rio Pequeno, brejo, 4 Mar 1980, G. Hatschbach 42775 (MBM); Rio Pequeno, 27 Apr 1988, G. Hatschbach 51984 w/J. Cordeiro (BM, S); Rio Pequeno, brejo, solo turfoso, 23 Nov 1989, V. Nicolack 87 w/J. Cordeiro (W). Mpio. Texeira Soares; Florestal 29 km para leste de Curitiba, estrada C[uritiba]-Paranaguá, campo limpo, em lugares aguados num corrego pantanoso, isolado e raro, 12 Dec 1947, G. Tessmann 2741 (NY).

Aloysia cordata is readily distinguished from all other members of the genus by its ternately arranged, sessile, sclerophyllous, cordate, and glabrous leaves with minutely scabrous margins. It is morphologically similar to A. polygalifolia Cham. and A. brasiliensis Moldenke since all have ternately arranged, somewhat sclerophyllous leaves with strongly to weakly revolute margins. However, the former taxon has sessile, truncate to subcordate, and adaxially scabrous leaves while the latter has petiolate, rounded to acute, and adaxially scabrous leaves. Aloysia cordata is endemic to the eastern part of the state of Paraná, Brazil in the area between the cities of Curitiba and Paranaguá in low elevation marshy or swampy habitats, usually in riverine settings. It flowers in the early part of the summer fromOctober to January and is reportedly rare when encountered (Hatschbach 20792, 11896, and Tessmann 2741).

Type: PERU. Cajamarca: Mpio. Cajamarca; sobre el km 156 de la carretera Pacasmayo-Cajamarca, bosque espinoso, 2000 m, 5 Apr 1982, I. Sanchez Vega 2763 (holotype: F!; isotypes: MO!, SI!).

Aloysia scorodonioides similis; ramulis velutinis, gracilibus; foliis oppositis; laminis ovatis vel ellipticis, 3.5–6.0 cm longis, 1.7–5.0 cm latis, supra velutinis, infra incanis; inflorescentiis paniculiformibus terminalibus, rachidibus incanis; schizocarpis bilobis, apicem setulosis.

Similar to Aloysia scorodonioides; stems velutinous, gracile; leaves opposite; laminae ovate to elliptic, 3.5–6.0 cm long, 1.7–5.0 cm wide, adaxially velutinous, abaxially incanous; inflorescence paniculate, terminal, rachis incanous; schizocarp bilobed, apex setose.

Shrub 1.0–1.5 m in height. Leaves opposite; petioles 0.3–1.0 cm long; laminae ovate to elliptic, 3.5–6.0 cm long, 1.7–5.0 cm wide, margins crenate, basally truncate to rounded, apically rounded, obtuse, to subacute, adaxially velutinous, abaxially incanous. Inflorescence loosely paniculate, composed of spicate racemes, terminal, determinate; peduncle 1–3 cm long, incanous; rachis 8–15(-25) cm long, incanous; pedicels 0.2–0.5 mm long. Bracts reduced, lanceolate, midrib present, 2.0–2.5 mm long, 0.3–0.5 mm wide, acuminate, strigulose, margins prominently ciliate. CALYX weakly zygomorphic, tubular, 2.0–2.5 mm long, densely setose with an understory of subsessile, glandular trichomes; lobes 4, trullate, acute to short acuminate. Corolla subactinomorphic, white; tube 2.5–3.0 mm long, pubescent with understory of subsessile, glandular trichomes, at least distally; limb 2.5–3.5 mm wide, basally pubescent with an understory of sub-sessile, glandular trichomes. Stigma sub-capitate, laterally disposed. fruit obovoid, 1.5–2.0 mm long, 1.0–1.5 mm wide, apically setulose, bilobed, lobes 0.1–0.3 mm long; intermericarpal cavity reduced, the surface papillate.

Additional Specimens Examined: PERU. Cajamarca: Mpio. Cajamarca; km 131 on Highway from near Pacasmayo to Cajamarca, low dense forest on steep limestone slopes, 1000–1500 m, 4 Jan 1983, W. D. Stevens 22046 (K, MO). Mpio. Contumazá; ca. 2 km from Contumazá on route to Cascas, 2620 m, 15 Apr 1986, M. O. Dillon et al. 4544 (F); alrededores de Contumazá, ladera, 2600 m, 25 May 1981, A. Sagástegui A. et al. 9843 (GH, MBM, MO, SI); alrededores de Contumazá, ladera, 2650m, 15 Apr 1994, A. Sagástegui A. et al. 15634 (F); alrededores de Contumazá, salida a Chilete, ladera, 2700 m, 5 Apr 1996, A. Sagástegui A. et al. 15867 (F); sobre la ruta Contumazá-Chilete, cerca a la Fila de las Pencas, ladera de arbustos, 2700–2750 m, 3 Jul 1983, I. Sánchez Vega 3170 (F).

Aloysia velutina is distinctive in having an inflorescence composed of indeterminate spicate racemes arranged into a terminal paniculate synflorescence; a similar structure is seen in only three other species: A. citrodora, A. fiebrigii, and A. herrerae. The latter taxa have little else in common with the novelty and are readily distinguished by the characters used in the key. The species most similar morphologically to A. velutina is A. scorodonioides, which it is distinguished by inflorescence structure, fruit morphology and overall pubescence. The former taxon has a terminal paniculate synflorescence, apically pubescent mericarps and densely velutinous to incanous vestiture, the latter has solitary inflorescences of spicate racemes arranged along the distal portion of an indeterminate branch, glabrous mericarps and strigulose to scabrous pubescence. The novelty is endemic to the dense woodlands in the area from Contumazá north to Chilete, Cajamarca, Peru at elevations of 2000–2800 m. It flowers in the fall from April to July and at least one collector reports it is locally common (Sanchez Vega 2763 and 3170).