Zygocarpum

Taxonomy

Zygocarpum M. Thulin & M. Lavin Syst. Bot. 26(2): 308. 2001.

Subfamily: Faboideae.
Phylogenetic Number: 3.14.01A.
Tribe: Aeschynomeneae.
Species Studied - Species in Genus: 0 studied; 6 in genus.

Description

Fruit: A lomentloment:
usually dry fruit derived from a single carpel that breaks transversely into one-seeded fruit segments
(or a lomentloment:
usually dry fruit derived from a single carpel that breaks transversely into one-seeded fruit segments
segment); 7–13 cm wide; with deciduous androecial sheath; with deciduous corolla; with deciduous calyx; without orifice formed by curving of fruit or fruit segments; straight; not plicate; not twisted; symmetrical; oblong; not inflated; with beak; straight; rounded at apex; aligned with longitudinal axis of fruit; rounded at base; aligned with longitudinal axis of fruit to oblique with longitudinal axis of fruit; margin constricted; margin constricted along both margins to slightly constricted along both margins; margin without sulcus; margin plain; wing(s) absent; stipitate to substipitate; with the stipe 2–11 mm long; indehiscent. Replum invisible. Lomentloment:
usually dry fruit derived from a single carpel that breaks transversely into one-seeded fruit segments
an intact article; indehiscent; segments (articles) conspicuous; segments (articles) 10–18 mm long; segments (articles) widest across seed area; segments (articles) with apical 1 different shape than middle one(s) and basal 1 different shape than middle one(s); segments (articles) oblong to elliptic. Epicarp glabrous, or pubescent and indurate; with hairs erect, or appressed; with 1 type of pubescence, or 2 types of pubescence; densely appressed pilose, or puberulent; with simple hairs, or simple hairs and glandular hairs; with hair bases plain, or swollen (and glandular); eglandular, or glandular; with glandular hairs; without spines; not smooth; with elevated features; veined; longitudinally veined relative to fruit length, or reticulately veined; not tuberculate; without embedded tissue, much thicker than epicarp, running from base to apex. Seed(s) 1–4; in 1 series.

Seed: Ca. 4 mm long; ca. 2 mm wide; not overgrown; not angular; asymmetrical; C-shaped. Testa present. Pleurogram absent. Pseudopleurogram absent. Hilum present; larger than punctiform; ca. 0.5 mm long; with curved outline; elliptic.

Distribution

Western and eastern Yemen, Western Oman, Socotra, and Somalia.

Old World; Southwest Asia and Africa (western and eastern Yemen, western Oman, Socotra, and Somalia).

Generic Notes

Thulin and Lavin (2001) separated this genus from Ormocarpum (3.14.01) using morphological and DNA evidence. No specimens were available for study, so the limited data were extracted from their publication.

Tribal Notes

Tribe Aeschynomeneae

Rudd (1981a) recognized four subtribes of Aeschynomeneae: Ormocarpinae V.E. Rudd (genera 3.14.01–3.14.08), Aeschynomeninae (genera 3.14.09–3.14.16), Discolobinae (A.E. Burkart) V.E. Rudd (genus 3.14.17: Discolobium), Poiretiinae (A.E. Burkart) V.E. Rudd (genera 3.14.18–3.14.21), and Stylosanthinae (G. Bentham) V.E. Rudd (genera 3.14.22–13.4.26). Tribal and subtribal placement of Diphysa is based on Lavin (1987; Polhill, 1994a, 1994b), and not on Polhill and Sousa (1981), who placed Diphysa in Robinieae. Bailey et al. (1997), using the chloroplast rpl2 intron and ORF184, suggested that Brya (11.01), Cranocarpus (11.02), Phylacium (11.22), and Neocollettia (11.26) are not members of Desmodieae (11) and that they probably belong in Aeschynomeneae.