Mucuna argyrophylla Standl., Contr. U.S. Natl. Herb.

De, Tânia M., Lewis, Gwilym P., Mansano, Vidal F. & Tozzi, Ana M. G. A., 2018, A revision of the neotropical Mucuna species (Leguminosae-Papilionoideae), Phytotaxa 337 (1), pp. 448-450 : 448-450

3. Mucuna argyrophylla Standl., Contr. U.S. Natl. Herb. 23(2): 504. 1922. ( Fig. 4 )

TYPE:— MEXICO, Chiapas , table-land about Ocuilapa, elev. 3400–3800 feet, 21 August 1895 (fl.) Nelson 3060 (holotype: US!) .

Liana. Leaves 3-foliolate; pulvinus 10 × 3.0 mm; petiole 5.5–11.7 cm long; stipels persistent; rachis (1.0) 2.0 (–2.5) cm long; petiolules 5.0–8.0 mm long; lateral leaflets 9.7–13.7 × 5.5–9.2 cm, asymmetric at base, acute to cuspidate at apex; apical leaflets elliptic, 8.0–14.5 × 5.5–9.0 cm, acute to rounded at base, acute to cuspidate at apex; venation eucamptodromous, secondary veins in 5.0–7.0 pairs per leaflet; dense, adpressed argenteous hairs on abaxial surface; less dense adaxially. Inflorescence axillary, pseudoracemose; peduncle ca. 1.0 m long; bracts and bracteoles not seen; rachis 3.0–5.0 cm long; brachyblasts nodose, internodes 2.0–3.0 mm; pedicels 2.2–6.0 cm long. Flowers 4.0– 5.5 cm long; calyx sericeous, 1.8–2.0 cm long, 4–lobed, the adaxial lobe formed by two connate sepals, 2.0 mm long, rounded at apex, the lateral lobes very discrete, ca, 1.0 mm long, acute at apex, the abaxial one 3.0 × 2.0 mm, rounded at apex; corolla reported to be pale lavender and white (D.E. Breedlove 20217 MO), greenish-yellow (E. Contreras 6248 MO), greenish-white (M.T. Germán et al. 1056 MO), white (R. Cedillo 3690 MO), greenish ( W.A. Schipp 131 MO), or pale yellow (D.E. Breedlove 26330 MO); standard broadly elliptic, 2.0–3.5 × 1.5–2.0 cm, attenuate at base, emarginate at apex, claw 6.0–7.0 mm long; wings oblong, 2.0–3.5 × 0.5 cm, attenuate at base, rounded at apex, the claw 8.0 mm long; keel petals oblong, 3.5–5.0 × 1.5 cm, attenuate at base, obtuse at apex, the claw 8.0 mm long; pubescent at base of wing and keel petals. Stamen filaments reported to be white (H.E. Moore & G.S. Bunting 8943 US), 3.2–3.5 cm long, glabrous. Gynoecium 3.0–5.0 cm long; style ca. 2.0 cm long, sericeous, except at apex; ovary 7.0–10 × 2.0 mm, sericeous; stigma peltate, villous. Fruits 11–21 × 3.5–5.0 cm, not ornamented by lamellae, covered with dense hairs, acute at base, cuspidate at apex, 1–4-seeded. Seeds globose, black, 13.1–3.3 × 2.7–2.8 × 1.1–1.3 cm; hilum black, 8.0 cm long × 2.0 mm high, circling ca. 80% of the seed circumference.

12 • Phytotaxa 337 (1) © 2018 Magnolia Press

MOURA ET AL.

Taxonomic notes:— One of the most noteworthy characteristics of M. argyrophylla is the argenteous hairs on the abaxial surface of the leaflets (a characteristic that also occurs on the leaflets of the pseudo-umbellate species M. argentea , as commented thereunder). Mucuna argyrophylla is morphologically more similar to M. holtonii ( Kuntze 1891: 207–208) Moldenke (1933: 7) , but the two species differ by the presence of silver, adpressed hairs on the abaxial surface of the leaflets of M. argyrophylla (vs. golden, erect hairs in M. holtonii ).

Phenology:— Flowering August to November; fruiting throughout the year.

Distribution and habitat:— North and Central America ( Mexico to Nicaragua) ( Fig. 5 ). It occurs in a number of different habitats including: tall evergreen forest, cloud forest, riverine vegetation and deciduous forest, and in areas under different levels of disturbance. The elevational range of the species is 25–1600 m.

Conservation status:— Although the reduced area of occupancy of M. argyrophylla is <500 km 2, it occurs in a number of localities in Belize, El Salvador, Guatemala, Honduras, Mexico, and Nicaragua, some within protected areas. Therefore, following the IUCN criteria (2016) we are ranking this species as being of Least Concern (LC).

Vernacular names: — ‘ Alampepe’, ‘bejuco tecalate’, ‘pica pica’, ‘tagala’ [ Mexico, Veracruz (S.G. Medellín 243 XAL; B. Dorantes 3562 MO; R. Cedillo 3690 MO; J. Arellano 129 XAL]; ‘casco de burra’ [ Mexico (G.I. Manriquez & S. Sinaca 2069 MO, XAL)]; ‘Pa-Chu’ [ Belize, Cayo (M.J. Balick et al. 1778 NY, US)]; ‘dinero del diablo’ [ Mexico, Puebla (P. Barsuto & G. Durán 753 MO, XAL)]; ‘horse eye’ [ British Honduras, Middlesey (P.H. Gentle 3063 A)].

Representative specimens examined:— BELIZE. Belize: 5 miles S of Belmopan, Hummingbird , highway, 22 January 1974 (fr.), J.D. Dwyer & R. Liesner 12122 ( MO) . Cayo: ca 15 km SW of San Ignacio in village San Antonio, in village San Antonio , 13 November 1987 (fr.), M.J. Balick et al. 1778 ( NY, US) . GUATEMALA. Alta Verapaz: Cubilquitz , December 1900 (fl.), H.V. Tuerckheim 7740 ( GH, US). Izabal: vicinity of Quiringuá, 15 May 1922 (fr.), P.C. Standley 24488 ( GH, NY, US). Peten: La Cumbre, km 137/138 on Cadenas Road, in low forest, 26 September 1966 (fl.), E.Contreras 6248 ( MO) . HONDURAS. Mullins River, 20 April 1929 (fr.), W.A. Schipp 131 ( BM, GH, K, MO, NY, US). Middlesey: 26 October 1939 (fl.), P.H. Gentle 3063 (A). San Antonio: 22 September 1928 (fl.), H.C. Sampson 19 (K) . MEXICO. Acapulco: October 1894 (str), E. Palmer 532 (K). Chiapas: a 30 km al E de Palenque, carretera Azul-Palenque , 4 March 1985 (fr.), E. Cabrera et al. 1918 ( BM, XAL) ; en los arredores de la zona Arqueologica Palenque , 27 September 1983 (fl.), E. Cabrera et al. 5606 ( IEB, MO, XAL) ; along road from highway 195 to Simojovel de Allend , 16 February 1979 (fr.), T.B. Croat 47705 ( MO) ; Berriozábal, 13 km N of Berriozábal, near Pozo Turipache and Finca el Suspiro , 9 October 1971 (fl.), D.E. Breedlove 20217 ( MO) ; 24 July 1972 (fl.), D.E. Breedlove 26330 ( MO) ; Ococingo, en boca Lacantum sobre el río Lacantum , 10 December 1984 (fr.), E. Martinez 9672 ( MO, US). Cordova: La Luz, Cordova, 30 September 1882 (fl.), E. Kerber 56 ( BM, K, US, W). Oaxaca: Ixtlán, La esperanza, bosque mesofilo de montaña, 12 June 1988 (fl.), R.L. Luna & G.J. Martín 314 ( MEXU, MO) ; Ixtlan, Ixtlan de Juarez, camino real de Tiltepec a Tierra caliente, 28 November 1999 (fr.), J.C . Flores et al. 95 ( IEB) ; Juchitán, camiño a la Gloria al SE de, St. María Chimalapa , 30 August 1984 (fl.), R. Torres & C. Martinez 6062 ( BM, MO, NY) ; Tuxtepec, San Lucas Ojitlán, a 1 km antes del poblado de Canton , entrada por la presa Cerro de Oro , 4 April 1989 (fr.), J.I. Calzada 14721 ( MEXU) ; Mixe, Novo Centro , vegetação muito alterada de selva alta perenifolia, 31 October 1977 (fl.), M. Sousa 8800 ( NY) . Puebla: Sierra Norte , selva mediana subperenifolia, 19 October 1980 (fr.), P. Basurto & G. Durán 753 ( MO, XAL) . Tabasco: Ranchería Belém , 16 km el NE of Macuspana, 8 October 1979 (fl.), M.T. Gérman et al. 1056 ( MO) . Veracruz: km 12 del camiño Cedillo- FCO, Villa Hidalgotitlan , 30 September 1974 (fl.), B. Dorantes 3562 ( MO, XAL) ; San Andres Tuxtla, Estación Biológica Tropical los Tuxtla , 8 October 1986 (fl.), R. Cedillo 3960 ( IEB, MO, XAL) ; 10 October 1984 (fl.), G.I. Manriquez & S. Sinaca 2069 ( MO, MEXU, XAL) ; rocky wooded slopes NW of Misantla, 2.4 miles on road to Martinez de la Torre, 28 September 1961 (fl.), H.E. Moore & G.S. Bunting 8943 ( US); Papantla, Plan Hidalgo , 21 April 1986 (fr.), S.G. Medellín 243 ( XAL) ; Acayucan, colonia Hidalgo , 15 November 1977 (fr.), J. Arellano 129 ( XAL) . NICARAGUA. Atlántico Sur: Región de La Esperanza, Río Grande , 12 April 1949 (fl.) A. Molina R. 2191 ( MO) .

Figures

FIGURE 4. Mucuna argyrophylla. A—Leaf and inflorescence. B & C—Details of stipels. D—Inflorescence. E—Gynoecium. F—Androecium: staminal sheath and one free stamen. G—Standard. H—Wing. J—Keel petals. K—Calyx opened out, outer surface. L—Fruit. (B, C and L drawn from: E. Martinez 9672 MO; A, D–K: M.T. Germán et al. 1056 MO). Drawn by Ana Lucia Souza.

FIGURE 5. Geographical distribution of four neotropical species of Mucuna: M. argyrophylla (Mexico and Central America), M. mitis (endemic to South America); and M. holtonii and M. mutisiana (distributed from Mexico to NW South America, the latter also occurring in the Dominican Republic).