Dewevrea

Taxonomy

Dewevrea M. Micheli Bull. Soc. Roy. Bot. Belgique 37: 47. 1898.

Subfamily: Faboideae.
Phylogenetic Number: 3.7.
Tribe: Millettieae.
Species Studied - Species in Genus: 1 studied; ca. 1 in genus, or 2 in genus.

Description

Fruit: A legume; unilocular; 15–17 cm long; 2.5–3 cm wide; 2–9 times longer than 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; asymmetrical; narrowly obovate; with both sutures parallelly curved; not inflated; compressed to flattened; with beak; straight; with solid beak the same color and texture as fruit; tapered at apex; aligned with longitudinal axis of fruit; long tapered at base; aligned with longitudinal axis of fruit; with the apex and base uniform in texture; ligneous; seed chambers externally invisible; margin not constricted; margin without sulcus; margin embellished; margin with ridge(s), or 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 but soon deciduous; with hairs erect; with 1 type of pubescence; sparsely velutinous; with pubescence brown; with pubescence uniformly distributed; with simple hairs; stiff; with hair bases swollen (slightly); eglandular; without spines; not smooth; with elevated features; veined (immature fruit), or not veined (mature fruit); reticulately veined; not tuberculate; lenticular (mature fruit); not exfoliating; with cracks; cracking oblique to fruit length; without embedded tissue, much thicker than epicarp, running from base to apex. Mesocarp present; thick; 2-layered, or 3-layered; without balsamic vesicles; without fibers; without reniform canals; with vitriol layer over solid layer; with vitriol layer over 2 distinct solid layers; ligneous. Endocarp present; visible; dull; opaque; mottled; brown; with mottling more or less uniform (dark); with brown overlay; smooth and floury-filamentous; without adhering pieces of testa; nonseptate; chartaceous; not exfoliating; remaining fused to mesocarp and epicarp; without wings; entire. Seed(s) 2–5; length parallel with fruit length; neither overlapping nor touching; in 1 series. Funiculus ca. 2.5 mm long; of 1 length only; thick; broadly triangular. Aril present; dry; when dry rim-aril and tongue-aril; entire; brown.

Seed: 24.5–26 mm long; 16.5–20 mm wide; ca. 8 mm thick; not overgrown; angular, or not angular; symmetrical; oblong, or ovate; 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; not smooth; with elevated features; wrinkled; chartaceous. Pleurogram absent. Pseudopleurogram absent. Fracture lines absent. Rim absent. Wing(s) absent. Raphe visible; from hilum through lens to base of seed and terminating; not bifurcating; darker than testa; darker brown; raised. Hilum present; fully concealed; concealed by funicular remnant; larger than punctiform; 6–6.5 mm long; with curved outline; narrowly elliptic; apical according to radicle tip but marginal according to seed length; flush; within rim; rim color darker than testa. Lens discernible; ca. 4 mm long; with margins straight; oblong; not in groove of raphe; confluent with hilum; mounded; similar color as testa; darker than testa; not within corona, halo, or rim. Endosperm absent. Cotyledons not smooth; convoluted; both outer faces convex; both the same thickness; both more or less of equal length; not folded; margin not entire 180 degrees from base of radicle; notched (strongly to shallowly); similar at apex; partially concealing radicle; notched at radicle, or split over radicle; with lobes; with lobes not touching; without basal groin formed by lobes; with the interface division terminating at base of radicle; without margins recessed; brown; inner face wrinkled; glabrous on inner face. Embryonic axis right angled; perpendicular to length of seed; without a joint evident between the radicle and the cotyledons. Radicle differentiated from cotyledon; triangular; lobe tip straight; straight with embryonic axis; centered between cotyledons; less than 1/2 length of cotyledons. Plumule rudimentary; glabrous.

Distribution

Equatorial West Africa.

Old World; Africa.

Tribal Notes

Tribe Millettieae

Geesink (1981) treated this tribe, as others before him, under the tribal name Tephroseae, but we now know that its correct name is Millettieae. Recent tribal studies (Geesink, 1981, 1984; Polhill, 1994a, 1994b) have arranged the genera in alphabetical order without phylogenetic numbers. Geesink (1984) monographed tribe Millettieae, and presented descriptive notes about fruits and seeds and in situ fruit and seed drawings. However, we are not entirely following Geesink (1984) for generic parameters because he either questioned the status of many of his new genera or did not make the necessary species transfers. The few new genera which he clearly recognized are being accepted. Lavin et al. (1998) developed a preliminary infratribal classification of six informal groups using phytochrome nucleotides: Millettia group, Lonchocarpus group, Derris group, Tephrosia group, "primitive" group, and Phaseoleae group. Lavin (1987) transferred Sphinctospermum to Millettieae. Lavin and Doyle (1991) carried out cladistic analyses integrating morphological and chloroplast DNA data, and concluded that it is a member of Robineae where we have placed it (now 8.12).