Genus Benthamia A.Rich.

(Figs 1; 2)

Monographie des Orchidées des Îles de France et Bourbon (Richard 1828: 37), non Lindl. (w).

Rolfeella Schltr., Repertorium Specierum Novarum Regni Vegetabilis 33: 18 (Schlechter 1924). — Type species: Benthamia glaberrima (Ridl.) Schltr.

TYPE SPECIES. — Benthamia latisatis (Thouars) Bytebier (as Benthamia latifolia A.Rich.).

DISTRIBUTION AND ECOLOGY. — The genus Benthamia is widespread in Madagascar, La Réunion and Mauritius, with possibly one species (probably B. africana (Lindl.) Hermans) on the Comoros (Fig. 3). It ranges from sea level to high altitudes (2600 m). It is generally found in open places, both dry and marshy.

ETYMOLOGY. — Named for the English botanist George Bentham (1800-1884), who together with Sir Joseph Hooker produced Genera Plantarum (1865-1883).

DESCRIPTION

Terrestrial or less commonly epiphytic (5 species) sympodial glabrous herbs with 2-7 swollen generally glabrous tubers, which are in fact tuberous roots. Stem erect or arcuate, sometimes with sheaths only (one species), or with 1-2 radical sheathing leaves, or with 2-10 cauline leaves. Leaves lanceolate, ovate or elliptic, sometimes not developed at anthesis (3 species). Rachis terminal, erect or rarely curved, few- to densely many-flowered. Floral bracts small, usually as long or longer than the ovary. Ovary pedicellate, fusiform or oblong, generally twisted (except Benthamia bosseri). Flowers small, resupinate (except one species with non-resupinate and pendent flowers), arranged in a narrow rachis, white, green or yellow; sepals and petals free or almost free, entire; labellum entire or trilobed; spur cylindrical (nine species) or short and scrotiform, entire or bilobed at apex, or a small hollow only in one species (B. boiteaui). Column short and massive, subterete, erect; anther erect to slightly deflexed, placed above the rostellum, apiculate or not, bilocular, locules parallel, without anther canals; pollinia two, ellipsoid, granular, 2 caudiculae rudimentary, with two viscidia, detachable, flat, ovate or subelliptic; rostellum small, tridentate or trilobed at the anterior edge; stigma always very short, cushion-shaped, with short convex lobes; auricles two, generally conspicuous, subspathulate or falciform, sometimes lacerated, on lateral sides of column. Fruit a dehiscent capsule, with floral parts persistent on the fruit.