Camptosema

Taxonomy

Camptosema W.J. Hooker & G.A.W. Arnott Bot. Misc. 3: 200. 1 Mar 1833.

Subfamily: Faboideae.
Phylogenetic Number: 3.10.24.
Tribe: Phaseoleae.
Subtribe: Diocleinae.
Species Studied - Species in Genus: 7 studied; 12 in genus.

Description

Fruit: A legume; unilocular; (4–)5–15 cm long; 0.6–1.4 cm wide; 0.2–0.3 cm thick; 2–9 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; asymmetrical, or symmetrical; linear, or falcate; with both sutures parallelly curved; not inflated; compressed; with beak; with solid beak the same color and texture as fruit; tapered at apex; aligned with longitudinal axis of fruit, or oblique with longitudinal axis of fruit, or right-angled with longitudinal axis of fruit; tapered at base; oblique with longitudinal axis of fruit; with the apex and base uniform in texture; coriaceous; seed chambers externally invisible; margin not constricted; margin without sulcus; margin plain, or embellished; margin with thickened sutural areas; wing(s) absent; nonstipitate, or stipitate (rarely); with the stipe 5–7 mm long; 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; black; with surface texture uniform; pubescent and indurate; with hairs erect; with 1 type of pubescence; puberulent, or velutinous, or sericeous; with pubescence golden, or white; with pubescence uniformly distributed; with simple hairs; pliable; with hair bases plain; eglandular; without spines; not smooth; with elevated features; not veined; not tuberculate; rugose, or scaly; 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; 1-layered; without balsamic vesicles; without fibers; without reniform canals; solid; coriaceous. Endocarp present; visible; dull; opaque; monochrome, or mottled; brown; with brown overlay; smooth and floury-filamentous; without adhering pieces of testa; septate, or nonseptate; with septa thin (tissue paper-like), flexible; with septa eglandular; chartaceous; exfoliating, or exfoliating in part; remaining fused to mesocarp and epicarp; without wings; entire. Seed(s) 3–14; length transverse to fruit length (some round); neither overlapping nor touching; in 1 series. Funiculus 1–2 mm long; of 1 length only; flattened; straight. Aril present; dry; when dry rim-aril, or tongue-aril; entire; covering less than 1/2 of seed; tan.

Seed: (4.5–)8–9.6 mm long; 5.5–7.2 mm wide; 2.3–6 mm thick; not overgrown; not angular; symmetrical; elliptic, or ovate; terete, or 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; brown; glabrous; smooth; coriaceous. 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 the same color as the rest of the hilum; larger than punctiform; 1.5–2.8 mm long; with curved outline; oval; subapical to radicle tip, or marginal according to radicle tip; recessed; within rim and within halo; halo lighter than testa; rim color darker than testa. Lens discernible; 0.1–0.8(–2) mm long; with margins straight; linear; not in groove of raphe; confluent with hilum; flush; dissimilar color from testa; darker than testa; dark brown; not within corona, halo, or rim. Endosperm present; thin, or trace; not pluglike and not resembling tip of radicle; restricted to region of embryo, or covering at least 1/2 of embryo, but not entire 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; entire 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 oblique to right angled; oblique to length of seed to perpendicular 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 rudimentary; glabrous.

Distribution

South America.

New World; South America; Argentina and Brazil.

Generic Notes

Burkart (1970) revised the four species of Argentine Camptosema.

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.