Disperis trilineata Schltr., 2002

Croix, Isobyl la, Bosser, Jean & Cribb, Phillip J., 2002, The genus Disperis (Orchidaceae) in Madagascar, the Comores, the Mascarenes and the Seychelles, Adansonia (3) 24 (1), pp. 55-87 : 58

2. Disperis trilineata Schltr.

Feddes Repert. Spec. Nov. Regni Veg. Beih. 33: 112 (1925); H. Perrier in Humbert H. (ed.) , Fl. Madag., 49 e fam., Orchidées 1: 181 (1939); Du Puy et al., Orch. Madag.: 136 (1999). — Type: Perrier de la Bâthie 15705, Madagascar, Sambirano valley (holo-, P!, photo K!) .

Slender terrestrial herb 5-15 cm high. Tubers 2, oblong, villous. Leaves 2, at about the middle of the stem, opposite or subopposite, 1.5-4 × 0.8- 1.8 cm, ovate, acute, with 3 pale longitudinal veins. Inflorescence 1-3-flowered; bracts 4 × 5 mm, broadly ovate. Flowers dull pink or violet, rather small; pedicel and ovary c. 11 mm long. Dorsal sepal 3-4 mm long, linear; lateral sepals 3-4 mm long, free more or less to the base, obliquely elliptic, each with a conical short spur around the middle. Petals 3-4 mm long, elliptic, with the median vein prominent on the outer surface, adnate to the dorsal sepal to form an open hood. Lip 4 mm long, fused to the column at base then with an obcuneiform claw bearing at the top a 5-lobed appendage, the side lobes short and farinose-tomentose, the mid-lobe larger, lanceolate and glabrous. Rostellum suborbicular, completely covering the anther. — Fig. 1.

DISTRIBUTION. — Madagascar, Comores. HABITAT. — In humus in moist forest; c. 400 m.

MATERIAL STUDIED. — MADAGASCAR: Perrier de la Bâthie 15705, Sambirano, sides of the valley, Jan. 1923 ( P!). — COMORES: Humblot 1484, Anjouan, 9 Mar. 1896 ( P!) .

This is a small delicate species of dark and humid forests at low elevation, found once in Madagascar and once on Anjouan in the Comores. The leaf is dull green on the upper side with three main rose-pink veins, the lower surface is red-purple.