Michelsonia

Taxonomy

Michelsonia L.L. Hauman Bull. Séances Inst. Roy. Colon. Belge 23: 478. Oct 1952.

Subfamily: Caesalpinioideae.
Phylogenetic Number: 1.4.57.
Tribe: Detarieae.
Group: Berlinia.
Species Studied - Species in Genus: 0 studied; 1 in genus.

Description

Fruit: A legume; unilocular; 7–10.5 cm long; 3.2–4.3 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; asymmetrical; obovate (to obtriangular, Weiringa 1999); with both sutures unequally curved; not inflated; flattened; with beak (1 mm long, with longitudinal vein running to beak), or without beak; straight; with solid beak the same color and texture as fruit; short tapered at apex; aligned with longitudinal axis of fruit; rounded at base; oblique with longitudinal axis of fruit; with the apex and base uniform in texture; ligneous (fruit very heavey, sinking in water, Weiringa 1999); seed chambers externally invisible; margin not constricted; margin without sulcus; margin embellished, or plain; margin with wing(s); wing(s) present; wing(s) 2; wing(s) 2–4 mm wide; wing(s) sutural; wing(s) on 1 suture (on uuper suture); substipitate; with the stipe 3–5 mm long; with all layers dehiscing (assumed); splitting along suture(s). Dehiscence of valves along both sutures; active. Replum invisible. Epicarp fairly glossy; monochrome; brown; with surface texture uniform; glabrous; eglandular; without spines; not smooth; with elevated features; veined; longitudinally veined relative to fruit length (with 1 strong longitudinal vein); not tuberculate; granulate; not exfoliating; without cracks; without embedded tissue, much thicker than epicarp, running from base to apex. Seed(s) 2; length parallel with fruit length (assumed); neither overlapping nor touching; in 1 series. Aril absent (assumed).

Seed: 17–20 mm long; 13–17 mm wide; not overgrown; not angular; symmetrical; elliptic to obovate; compressed. Testa present; without pieces of adhering epicarp; not adhering to endocarp; free from endocarp; fairly glossy; not modified by a bloom; colored; monochrome; medium brown; glabrous; chartaceous. Rim absent. Wing(s) absent.

Distribution

Eastern Zaire.

Old World; Africa (eastern Zaire).

Generic Notes

Wieringa (1999) mongraphed this genus. Gervais and Bruneau (2002) assessed Wieringa's claasification using molecular techniques, and their results agreed, in general, with those of Wieringa (1999). Seeds and entire fruits were not available for this study, so data were extracted from Weiringa (1999). Cowan and Polhill (1981b) reported that "insufficient material seen to assess the case for amalgamating Michelsonia with Tetraberlinia" (5.02).

Tribal Notes

Tribe Detarieae

Bruneau et al. (2000) carried out extensive phylogenetic analyses of tribes Amherstieae and Detarieae. They concluded that they form a single monophyletic group. Therefore, they supported Polhill's (1995a, 1995b) decision to unite the two tribes.