Disperis majungensis 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 : 73

13. Disperis majungensis Schltr.

Feddes Repert. Spec. Nov. Regni Veg. Beih. 33: 108 (1925); H. Perrier in Humbert H. (ed.) , Fl. Madag., 49 e fam., Orchidées 1: 190 (1939); Du Puy et al., Orch. Madag.: 135 (1999). — Type: Perrier de la Bâthie 13038, Madagascar, Majunga (holo-, P!, photo K!) .

Slender terrestrial herb 10-13 cm tall; tubers 16-20 × 12 mm, globose or ovoid. Leaves 2, sessile or with a short 2-3 mm long petiole, alternate, borne at about the middle of the stem, 2-4.3 × 1.2-2 cm, ovate, acute, dark green above, red below. Inflorescence 1-3-flowered; bracts (5-)8-16 × 6-8 mm, leafy. Flowers violet; pedicel and ovary 14 mm long. Dorsal sepal 6 × 0.8 mm, linear; lateral sepals free more or less to base, more or less 5 mm long, deeply saccate, with an obtuse spur 1.5 mm long. Petals 5.5-6 × 2-3 mm, more or less semicircular, adnate to the dorsal sepal and forming a shallow hood c. 5-6 mm long, 4.5 mm wide, with the dorsal sepal protruding slightly between the petals. Lip 4.5 mm long over all, with a claw 3 mm long, the basal 2 mm fused to the column; appendage 3- lobed, like a trident, the side lobes erect, 1.5- 1.8 mm long, conical with inrolled margins, like the fingers of a glove, densely shortly papillose-pubescent; mid-lobe triangular, obtuse, 2-2.3 mm long, flat, often bent over to the front, densely shortly papillose-pubescent. Rostellum arms 3 mm long, not enlarged at the tips. — Fig. 6A.

DISTRIBUTION. — Madagascar; endemic. HABITAT. — In humus, in rocky wood on calcareous soil; sea level- 100 m.

MATERIAL STUDIED. — W MADAGASCAR: Morat 4842, Antsingy of Antsalova, Res. Nat. no. 9, Jan. 1975 ( P!); Perrier de la Bâthie 13038, near Majunga, not far from the sea, Feb. 1920 ( P) .

This species is readily recognised by its very characteristic lip appendage. It is a rare species, collected only twice, the localities being very remote from each other.

Figures

Fig. 6. — Appendage of lip: A, Disperis majungensis (Perrier de la Bâthie 13038); B, Disperis cordata (Cadet C11, in alcohol); C, Disperis hildebrandtii (Hildebrandt 3158); D, Disperis ciliata (Humbert & Capuron 25002); E, Disperis lanceana (Lance s.n.); F, Disperis saxicola (Bosser 17168); G, Disperis humblotii (Humblot 1592); H; Disperis perrieri (Humbert & Capuron 25758); I, Disperis oppositifolia var. mascarenensis (Bosser 21622).