Otoptera

Taxonomy

Otoptera A.P. de Candolle Prodr. 2: 240. Nov (med.) 1825.

Subfamily: Faboideae.
Phylogenetic Number: 3.10.56.
Tribe: Phaseoleae.
Subtribe: Phaseolinae.
Species Studied - Species in Genus: 1 studied; 2 in genus.

Description

Fruit: A legume; unilocular; 7.7–10.5(–12) cm long; 0.5–1.1 cm wide; more than 9 times longer than wide; with deciduous androecial sheath; with deciduous corolla; with persistent calyx, or deciduous calyx; with calyx shorter than fruit; without orifice formed by curving of fruit or fruit segments; straight; not plicate; not twisted; symmetrical; linear; not inflated; compressed, or terete (Du Puy et al., 2002); without beak, or with beak (Du Puy et al., 2002); straight; with solid beak the same color and texture as fruit; long tapered at apex; aligned with longitudinal axis of fruit; tapered at base to rounded at base; aligned with longitudinal axis of fruit; with the apex and base uniform in texture; coriaceous; seed chambers externally invisible; margin not constricted, or constricted (Du Puy et al., 2002); margin slightly constricted along both margins; margin without sulcus; margin embellished; margin with slightly thickened sutural areas; wing(s) absent; nonstipitate; with all layers dehiscing; splitting along suture(s). Dehiscence of valves along both sutures; apical and down; active; with valves twisting. Replum invisible. Epicarp dull; monochrome, or multicolored; mottled; brown to tan, or gray (pale); with brown overlay; mottling color combination constant; with mottling over seed chambers; with surface texture uniform; glabrous, or pubescent and indurate; with hairs erect; with 1 type of pubescence; puberulent; with pubescence golden; with pubescence uniformly distributed; with simple hairs; pliable; with hair bases plain; eglandular; without spines; smooth, or not smooth; with elevated features; not veined; not tuberculate; wrinkled; not exfoliating; with cracks; cracking oblique to fruit length; without embedded tissue, much thicker than epicarp, running from base to apex. Mesocarp present; thick; surface not veined; 2-layered; with balsamic vesicles; without fibers; without reniform canals; with solid layer over spongy layer; coriaceous. Endocarp present; visible; dull; opaque; monochrome; tan to white; fibrous and scurfy; without adhering pieces of testa; nonseptate, or septate (Otoptera madagascariensis R. Vig., Du Puy et al., 2002); with septa thin (tissue paper-like), flexible; with septa eglandular; chartaceous; exfoliating in part; remaining fused to mesocarp and epicarp; without wings; entire. Seed(s) (2–)4–9; length parallel with fruit length; neither overlapping nor touching; in 1 series. Funiculus 0.5–0.6 mm long; of 1 length only; flattened; triangular. Aril present; dry; when dry tiny, hippocrepiform rim-aril; entire; cream.

Seed: 7–10 mm long; 4–5.8 mm wide; 2.8–5.3 mm thick; not overgrown; not angular; symmetrical; elliptic to oblong; terete to compressed; with surface smooth; without visible radicle and cotyledon lobes; without hilar sinus; without umbo on seed faces; without medial ridge on each face. Cuticle not exfoliating; not inflated; not wrinkled. Testa present; without pieces of adhering epicarp; not adhering to endocarp; free from endocarp; dull; not modified by a bloom; colored; monochrome, or mottled; with frequent mottles; dark to pale brown or brown; with brown overlay (darker); glabrous; smooth; coriaceous. Pleurogram absent. Pseudopleurogram absent. Fracture lines absent. Rim absent. Wing(s) absent. Raphe visible, or not visible; from hilum through lens and base of seed to point opposite hilum; not bifurcating; color of testa; raised. Hilum present; fully concealed; concealed by funicular remnant; without faboid split; larger than punctiform; 0.7–1 mm long; with curved outline; elliptic; apical according to radicle tip but marginal according to seed length; recessed; within rim; rim color darker than testa. Lens discernible, or not discernible; 0.8–1 mm long; with margins straight; linear; not in groove of raphe; confluent with hilum; recessed; similar color as testa; lighter than testa, or darker than testa; brown; within rim; rim color lighter than testa, or darker than testa. Endosperm absent. Cotyledons smooth, or not smooth; both outer faces convex; both the same thickness; both more or less of equal length; not folded; margin entire 180 degrees from base of radicle; similar at apex; not concealing radicle; notched at radicle; without lobes; with the interface division terminating at base of radicle; without margins recessed; yellow; inner face flat; glabrous on inner face. Embryonic axis oblique; oblique to length of seed; without a joint evident between the radicle and the cotyledons. Radicle differentiated from cotyledon; triangular; lobe tip straight; oblique to cotyledons; centered between cotyledons; less than 1/2 length of cotyledons. Plumule rudimentary; glabrous.

Distribution

Southern Africa.

Old World; Africa and Madagascar.

Generic Notes

Verdcourt (1971) gave a more exact distribution for this genus.

Tribal Notes

Tribe Phaseoleae

Bruneau et al. (1995) carried out cladistic analyses of tribe Phaseoleae using chloroplast DNA restriction site data. Their results indicated that the tribe is not monophyletic and that the tribal delimitations between Phaseoleae and Desmodieae (11) and between Phaseoleae and Millettieae (7) are problematic.