Dendrobium eriopexis Schlechter
Neville H.S. Howcroft

INTRODUCTION: Earlier this year a number of dried specimens of orchids were received at the Forest Reseach Institute, Lae, for identification. These specimens came from Misima Island and were lodged by Mrs Lorie Ryan whose husband works for the Mining company. Both of them are very interested in orchids and take every opportunity to collect orchids from the mining area.

Among the specimens received was an unusual specimen with a flattened stem and a single flower which looked as if it might belong to the genus Dendrobium and the section Grastidium. A check with the literature showed that the orchid belongs to a related section Eriopexis. Rehydrated flowers suggested that it could be one of two specimens. I was having difficulties because of the condition of those flowers and I need more material.

Chance came to the rescue. I visited Misima not long after for consultancy work. I met the Ryans and I met the plant which donated the specimen I had been examining at FRI. It was in flower and soI was able to add preserved specimens to our collection here. Once back at Lae I was able to complete my illustration of the orchid and conclude that the species was Dendrobium eriopexis Schltr.

DESCRIPTION: D. eriopexis Schltr., in K. Schum. et Laut., Nachtr. (1905), p.170, in Orchideen von Deutsch Neuguinea

Plant epiphytic, erect to semi-pendant, to c. 80 cm long, rhizomes very short; stems very compressed, densely foliaged, leaf sheaths always present, with sheaths c. 1 - 1.3 cm wide; leaf oblong elliptic, obtuse, base subpetiolate c. 15 cm long , 3 cm wide. Inflorescence subsessile, two flowered. Flowers white with column foot golden yellow, large, erect to patent, subopposite;dorsal sepal narrowly ovate-elliptic, obtuse glabrous 1.9 cm long, 1.25 cm wide, lateral sepals falcate, widest at bade forming a broad menum, 1.75 cm long, 1.33 cm wide, petal obliquely oblong spathulate, obtuse, glabrous, 1.58 cm long, 6.6 mm wide; labellum three lobed, subquadrate in outline, 1.16 cm long, 1.25 cm between lateral lobes when flattened, densely pilose on the disc, lobes incurved, obliquely rhombic with rounded, minutely serrulate margins, midlobe accuminate. Column short, apex conspicuously contracted, foot concave, extended, incurved. Cliandrium lobes small, obtuse with dorsal, one rounded at apex.

View drawing: Dendrobium eriopexis Schlechter

Key to illustration:  A - apical portion of plant stem with flower (5 cm scale), B - flower (10 mm scale), C - dorsal sepal, D - petal, E - lateral sepal, F - cut away view of flower showing labellum and column, G - labellum flattened, H - column, lateral view (4 mm scale), I - column, ventral view (4 mm scale)