Collaea

Taxonomy

Collaea A.P. de Candolle Ann. Sci. Nat. (Paris) 4: 96. Jan 1825.

Subfamily: Faboideae.
Phylogenetic Number: 3.10.26.
Tribe: Phaseoleae.
Subtribe: Diocleinae.
Species Studied - Species in Genus: 5 studied; 5 in genus.

Description

Fruit: A legume; unilocular; 4.2–13 cm long; 0.5–1 cm wide; 0.2–0.3 cm thick; 2–9 times longer than wide to more than 9 times longer than wide; with deciduous androecial sheath; with deciduous corolla; with persistent calyx; with calyx shorter than fruit; without orifice formed by curving of fruit or fruit segments; straight, or curved (slightly); not plicate; not twisted; symmetrical, or asymmetrical; linear; with both sutures nearly straight; not inflated; compressed; without beak, or with beak; straight; with solid beak the same color and texture as fruit; tapered at apex to short tapered at apex; oblique with longitudinal axis of fruit; tapered at base, or short tapered at base; aligned with longitudinal axis of fruit; with the apex and base uniform in texture; coriaceous; seed chambers externally visible, or invisible; margin not constricted; margin without sulcus; margin plain, or embellished; margin with 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; brown; with surface texture uniform; pubescent and indurate; with hairs erect; with 1 type of pubescence; velutinous, or sericeous; with pubescence golden, or white; with pubescence uniformly distributed; with simple hairs; pliable; with hair bases plain; eglandular; without spines; smooth; not veined; not tuberculate; not exfoliating; with cracks; cracking oblique to fruit length; without embedded tissue, much thicker than epicarp, running from base to apex. Mesocarp present; thin; surface not veined; 2-layered; without balsamic vesicles; without fibers; without reniform canals; with spongy layer over solid layer; coriaceous to chartaceous. Endocarp present; visible; dull; opaque; mottled; brown, or tan; with mottling over seed chambers; with brown overlay; scurfy; without adhering pieces of testa; septate; with septa thicker than paper, firm; with septa eglandular; chartaceous; exfoliating in part; remaining fused to mesocarp and epicarp; without wings; entire. Seed(s) 6–14; length transverse to fruit length; neither overlapping nor touching; in 1 series. Funiculus 0.5–6 mm long; of 1 length only; flattened; triangular. Aril present; dry; when dry rim-aril; entire to crenate; covering less than 1/2 of seed; without tongue (or flap) on lips of 2-lipped rim-aril, or with tongues (or flap) on lips of 2-lipped rim-aril; with 2 tongues or flaps, 1 on each lip of 2-lipped rim-aril; tan.

Seed: 7–8.8 mm long; 5–5.8 mm wide; 3.5–5 mm thick; not overgrown; not angular; symmetrical; oblong to ovate; 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; mottled; with frequent mottles; reddish brown; with brown overlay (dark); glabrous; smooth; chartaceous. Pleurogram absent. Pseudopleurogram absent. Fracture lines absent. Rim absent. Wing(s) absent. Raphe not visible. Hilum present; visible; with faboid split; with the lips of the faboid split lighter colored than the rest of the hilum and therefore conspicuous; larger than punctiform; 4–5 mm long; with straight outline; linear; subapical to radicle tip; raised; within rim, or within halo; halo darker than testa; rim color darker than testa. Lens discernible; 0.7–1.5 mm long; with margins straight; linear; not in groove of raphe; confluent with hilum; flush; dissimilar color from testa; lighter than testa; tan; within halo; halo color darker than testa. Endosperm present; trace; not pluglike and not resembling tip of radicle; restricted to region of embryo; adnate to testa. Cotyledons 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; partially concealing radicle; split over radicle; without lobes; with the interface division terminating at base of radicle; without margins recessed; tan; inner face flat; glabrous on inner face. Embryonic axis right angled; oblique to length of seed; without a joint evident between the radicle and the cotyledons. Radicle differentiated from cotyledon; linear; lobe tip straight; oblique to cotyledons; centered between cotyledons; less than 1/2 length of cotyledons. Plumule well developed; glabrous.

Distribution

South America.

New World; South America; Argentina.

Generic Notes

Generic delimitation follows Burkart (1971).

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.