Diagnostic description ²

Jacquemontia cayensis Britton in Britton & Millsp., Fl. Bahamas 349. 1920.

Fig. 73. A-C

Slightly woody vine, twining, much branched from the base, attaining 2 m in length. Stems slender, cylindrical, copper-brown, densely pubescent, with whitish stellate hairs. Leaves alternate or clustered on short axillary branches; blades simple, (1) 2-3 × 0.5-1.5 (2) cm, elliptical, ovate, obovate, or rounded, coriaceous or sub fleshy, the apex rounded or less frequently acute, emarginate and mucronate, the base acute, obtuse, or cuneate, the margins revolute, reddish, with stellate hairs; upper surface yellowish green, glabrous or with some scattered stellate hairs, the midvein sunken; lower surface yellowish green, dull, with a prominent midvein, covered with stellate hairs; petioles 5-12 mm long, reddish, densely covered with stellate hairs. Flowers arranged in simple dichasial cymes; peduncles ca. 4 mm long, stellate-pubescent; pedicels 6-8 mm long, stellate-pubescent. Calyx green, crateriform, the sepals ovate, 2.5-3 mm long, acute at the apex, the margins brown; corolla white, infundibuliform, ca. 1 cm long, deeply lobed, the lobes ovate, ca. 5 mm long; stamens white, exserted; stigmas white, bilobate. Capsule ovoid, ca. 4 mm in diameter, light brown, glabrous; seeds pyriform-triangular, 2-3 mm long, puberulous or glabrous.

Phenology: Collected in flower and fruit in mid-September.

Status: Native, uncommon.

Commentary: Jacquemontia cayensis can be confused with J. havanensis; both species are quite variable, to the point that it is difficult to identify some specimens as one species or the other. As a general rule, J. cayensis has leaves rounded at the apex and flowers clustered in reduced cymes. Jacquemontia havanensis, on the other hand, has leaves with acute or obtuse apices and the cymes contain 4 or more flowers.

Selected Specimens Examined: Acevedo-Rdgz., P. 7874; 10975; 11560; 11564; Liogier, A.H. 10794.

Distribution ³

Distribution: Along the south coast of Puerto Rico. Also on Mona and Anegada; the Bahamas, Cuba, and the Turks Islands.

Public forest: Guánica and Mona.

Sources and Credits

1. (c) Smithsonian Institution, National Museum of Natural History, Department of Botany, some rights reserved (CC BY-NC-SA), https://collections.nmnh.si.edu/services/media.php?env=botany&irn=10351000
2. (c) Pedro Acevedo-Rodríguez, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/28435251
3. (c) Pedro Acevedo-Rodríguez, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/28435774

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