Ramirezella

Taxonomy

Ramirezella J.N. Rose Contr. U.S. Natl. Herb. 8: 44. 16 Jun 1903.

Subfamily: Faboideae.
Phylogenetic Number: 3.10.66A.
Tribe: Phaseoleae.
Subtribe: Phaseolinae.
Species Studied - Species in Genus: 2 studied; 7 in genus.

Description

Fruit: A legumelegume:
usually dry, dehiscent fruit derived from a single carpel that opens along two longitudinal sutures
; unilocular; 10.5–16 cm long; ca. 1.3 cm wide; 0.3–0.5 cm thick; 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; symmetrical; narrowly oblong; not inflated; flattened; with beak (narrowly triangular, 17 X 3 mm, easily broken off); straight; with solid beak the same color and texture as fruit; tapered at apex; aligned with longitudinal axis of fruit; long tapered at base, or tapered at base; aligned with longitudinal axis of fruit; with the apex and base uniform in texture; chartaceous; seed chambers externally invisible; margin not constricted; margin with sulcus (shallow); margin plain; wing(s) absent; substipitate; with all layers dehiscing; splitting along suture(s). Dehiscence of valves along both sutures; apical and down (assumed); active; with valves twisting. Replum invisible. Epicarp dull; monochrome; tan to greenish tan; with surface texture uniform; glabrous; eglandular; without spines; not smooth; with elevated features, or recessed features; not veined, or veined (faintly); reticulately veined; not tuberculate; minutely slitted obliquely; not exfoliating; without cracks; 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 solid layer over solid layer; chartaceous. Endocarp present; visible; dull, or glossy (next to seeds); translucent, or opaque (next to seeds); monochrome; white, or tan; pithy, or spongy and smooth (next to seeds), or smooth; without adhering pieces of testa; septate, or subseptate; with septa thin (tissue paper-like), flexible; with septa eglandular; chartaceous; not exfoliating; remaining fused to mesocarp and epicarp; without wings; entire. Seed(s) 5–10; length parallel with fruit length; neither overlapping nor touching; in 1 series. Funiculus 2–3.6 mm long; of 1 length only; flattened; triangular. Aril present; dry; when dry tongue-aril; entire; covering less than 1/2 of seed; cream.

Seed: 5.5–9.5 mm long; 3–9 mm wide; 2.5–4.5 mm thick; not overgrown; not angular; symmetrical; circular, or elliptic; compressed, or flattened (rarely); 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, or glossy; not modified by a bloom; colored; mottled and streaked, or monochrome (rarely); with frequent streaks; dark or light brown; with dark or light brown overlay, or brown overlay and tan overlay; glabrous; not smooth, or smooth; with elevated features; wrinkled; chartaceous. Pleurogram absent. Pseudopleurogram absent. Fracture lines absent. Rim absent. Wing(s) absent. Raphe not visible. Hilum present; fully concealed; concealed by funicular remnant; with faboid split; with the lips of the faboid split lighter colored than the rest of the hilum and therefore conspicuous; larger than punctiform; 2–3 mm long; with straight outline, or curved outline; narrowly oval; linear; apical according to radicle tip but marginal according to seed length; recessed; within rim (sometimes weakly developed); rim color of testa. Lens discernible; 0.6–1.3 mm long; with margins straight; linear; not in groove of raphe; confluent with hilum; recessed; same color as testa, or dissimilar color from testa; darker than testa; dark brown; within rim; rim color of testa, or darker than testa. Endosperm absent. 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; not concealing radicle; notched at radicle; without lobes; with the interface division terminating at base of radicle; without margins recessed; light brown; 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; linear; lobe tip straight; oblique to cotyledons; centered between cotyledons; less than 1/2 length of cotyledons. Plumule well developed; glabrous.

Distribution

From Mexico to Nicaragua.

New World; Mexico and Central America (as far south as Nicaragua).

Generic Notes

Lackey (1981) noted that he preferred to merge Ramirezella into Vigna (10.66), and did so (Lackey 1983) without making the necessary new combinations. McVaugh (1987) also included Ramirezella in Vigna, and made some of the needed combinations. Maréchal et al. (1978) maintained Ramirezella as a good genus separate from Vigna. Morphological (Ochoterena-Booth 1991; Ochoterena-Booth and Delgado Salinas 1994) and chloroplast DNA (Delgado Salinas et al. 1993) studies have supported Ramirezella as a good genus. Therefore we have followed Maréchal et al., and not Lackey. The number of species and distribution are from Ochoterena-Booth and Delgado Salinas.

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.