Bergeronia

Taxonomy

Bergeronia M. Micheli Mém. Soc. Phys. Genève 28(7): 38. 1883.

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

Description

Fruit: A legume, or a loment (or a loment segment); unilocular; 3–8.5 cm long; 0.5–0.8 cm wide; 0.3–0.5 cm thick; 2–9 times longer than wide, or 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; curved to 0.5-coiled; not plicate; not twisted; asymmetrical; C-shaped and moniliform; with both sutures parallelly curved; not inflated; compressed; with beak; straight; with solid beak the same color and texture as fruit; short tapered at apex; oblique with longitudinal axis of fruit; short tapered at base; oblique with longitudinal axis of fruit; with the apex and base uniform in texture; coriaceous; seed chambers externally visible; seed chambers with the raised seed chambers not torulose; margin constricted, or not constricted; margin slightly constricted along both margins; margin without sulcus; margin plain; wing(s) absent; nonstipitate; indehiscent. Loment indehiscent; segments (articles) conspicuous; segments (articles) 10–15 mm long; segments (articles) widest across seed area; segments (articles) with apical 1 different shape than middle one(s) and basal 1 different shape than middle one(s); segments (articles) oblong. Epicarp dull; monochrome; brown; with surface texture uniform; pubescent and indurate; with hairs erect and appressed; with 2 types of pubescence; sericeous and villous; with pubescence tan; with pubescence uniformly distributed; with simple hairs; pliable; with hair bases plain to swollen (slightly); eglandular; without spines; not smooth; with elevated features; not veined; not tuberculate; dotted; not exfoliating; without cracks; without embedded tissue, much thicker than epicarp, running from base to apex. Mesocarp present; thin (thicker near sutures); surface not veined; 1-layered; without balsamic vesicles; without fibers; without reniform canals; solid; chartaceous. Endocarp present; visible; dull; opaque; mottled; tan; with mottling more or less uniform (dark); with brown overlay; scurfy and smooth; without adhering pieces of testa; septate; with septa thicker than paper, firm; with septa eglandular; chartaceous; not exfoliating; remaining fused to mesocarp and epicarp; without wings; entire. Seed(s) 1–7; length parallel with fruit length; neither overlapping nor touching; in 1 series. Funiculus of 1 length only; flattened; straight. Aril present; dry; when dry rim-aril; entire; cream.

Seed: 5–7 mm long; 4–4.5 mm wide; 2–2.5 mm thick; not overgrown; angular, or not angular; asymmetrical; oblong to reniform; compressed; 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; reddish brown; 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 the same color as the rest of the hilum; larger than punctiform; 1–1.3 mm long; with curved outline; circular to elliptic; apical according to radicle tip but marginal according to seed length; recessed; within rim; rim color darker than testa. Lens discernible; 0.7–1 mm long; with margins straight; narrowly triangular; not in groove of raphe; confluent with hilum; flush; similar color as testa; darker than testa; very dark brown; within halo; halo color darker than testa. Endosperm absent. Cotyledons smooth; both outer faces convex; both the same thickness; 1 longer than other; not folded; margin entire 180 degrees from base of radicle; similar at apex; not 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; oblique to length of seed; without a joint evident between the radicle and the cotyledons. Radicle differentiated from cotyledon; linear; lobe tip slightly curved; oblique to cotyledons; centered between cotyledons; less than 1/2 length of cotyledons. Plumule moderately developed; glabrous.

Distribution

Paraguay and northern Argentina.

New World; South America (Paraguay and Argentina); Argentina and Brazil.
 

Generic Notes

Micheli (1883) had excellent seed-fruit drawings.

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).