Disperis anthoceros var. humbertii (H.Perrier) la Croix, Adansonia, III, 24: 58 (2002).
Homotypic Synonyms:
Disperis humbertii H.Perrier, Notul. Syst. (Paris) 8: 35 (1939).
Slender terrestrial herb 8-15 cm tall. Tubers 2, c. 8 × 5 mm, ovoid. Leaves two, opposite, sessile, set about the middle of the stem, 13-22 × 11-16 mm, ovate, acute. Inflorescence 1-2-flowered; bracts leafy, c. 7 × 4 mm. Flowers white; pedicel and ovary 7-9 mm long. Dorsal sepal joined to petals to form a slender, erect spur 7-9 mm long from apex of spur to top of ovary; lateral sepals 7 × 3.5 mm, obliquely ovate, joined at the base for from quarter to half of their length, each with a sac-like spur c. 1 mm long, around the middle. Petals c. 7 × 4.5 mm, falcate, adnate to the dorsal sepal. Lip joined to column at base, then with a linear claw which almost reaches the tip of the spur, then is bent back for c. 1 mm, bearing at its apex an appendage of 2 fimbriate lobules 1-1.5 mm long.
The flowers of Disperis humbertii differ from those of Disperis anthoceros only in being slightly smaller. In the typical form of Disperis anthoceros, the spur is 12-20 mm long, while in var. grandiflora Verdc. from Tanzania, the spur is 23-30 mm long.
In ravine with bamboos, on basalt and sandstone.
NE. Madagascar