Dendrobium wisselense

Dendrobium wisselense P.J.Cribb, Orchadian 6 (1981) 279, fig. 2.

Type: Eyma 5385 (holo L, iso BO).

An erect, epiphytic or terrestrial herb to about 38 cm tall. Pseudobulbs slenderly clavate, 2-5-noded, 7-22 cm long, up to 8 mm diam., 2-leaved at the apex. Leaves coriaceous, suberect, linear to narrowly elliptic-oblong, minutely emarginate at rounded apex, up to 8-5 by 1.1.2 cm. Inflorescence erect or suberect, 8-16 cm long, 8-20-flowered; peduncle and rachis terete, slender; bracts lanceolate, acuminate, 2-3 mm long. Ovary verruculose, at right angles to the pedicel. Dorsal sepal lanceolate, acuminate, 12-13.5 by 3.5 mm; lateral sepals obliquely lanceolate, acuminate, 12-14 by 6 mm. Petals narrowly lanceolate, acuminate, 11-13.5 by 3 mm. Lip very obscurely 3-lobed, obovate-spathulate, apiculate, 14 by 7.5 mm; callus linear, 3-ridged, half the length of the lip, mid-ridge smaller than side-ridges. Column 2 mm long; filament 0.6 mm long; anther cap verruculose.
(after Cribb, 1983).

Colours: Flower cream colour.

Habitat: Epiphyte in primary Castanopsis-Nothofagus forest. Altitude 1100 to 1750 m.

Flowering time in the wild: November, January.

Distribution: New Guinea.

Distribution in New Guinea: Papua (Nabire and Sorong Regencies).

Map: WISSEMAP.JPG [Dendrobium wisselense P.J.Cribb, distribution map, redrawn from P. Cribb, Kew Bull. 38 (1983) 242, map 3 (with new record added).]

Notes: Dendrobium wisselense is readily distinguished from Dendrobium kauldorumii by its linear to narrowly elliptic-oblong leaves less than 1.2 cm broad and by its entire or sub-entire somewhat spathulate, apiculate lip with a three-ridged callus. It is also close to Dendrobium rariflorum, which however differs in having one-leafed pseudobulbs and a distinctly 3-lobed lip with an elliptic-angular midlobe.
(after Cribb, 1983).

Cultivation: Cool growing (requirements not known).