Dendrobium exasperatum Schltr., Repert. Spec. Nov. Regni Veg. Beih. 1 (1912) 583; 21 (1928) t. 194, fig. 729.
Type: Schlechter 16527 (holo B, lost).
Rhizome very short, roots elongated, filiform, flexuose, glabrous. Stems crowded, patent, slender, slightly laterally compressed, curved, up to 80 cm by 4 mm, densely many-leaved, unbranched. Leaf sheaths entirely covering the stem. Leaves erect-patent to patent, narrowly lanceolate, 8-10 by 0.8-1.1 cm, apex acute, upper surface shining. Inflorescences lateral from the stem, short, 2-flowered, spathe oblong, laterally compressed, obtuse. Floral bracts caducous. Pedicel and ovary 1.8 cm long, slender, glabrous. Flowers c. 4 cm across. Dorsal sepal lanceolate, 2.2 cm long, apex obtusely acuminate; outside covered with sharp papillae. Lateral sepals obliquely lanceolate, widened at the base, 2.2 cm long, outside covered with sharp papillae, apex obtusely acuminate; mentum short, obtuse. Petals obliquely linear, a little shorter than the sepals, apex elongated, much narrowed. Lip 3-lobed in the basal third, in outline oblong, 1.2 cm long, in basal third inside sparsely covered with papillae, with a linear keel extending from the base to above the base of the midlobe, on the midlobe with a dense cushion-like covering of hairs; lateral lobes falcate-triangular, small, obtuse; midlobe elliptic, margins unequally lacerate-pectinate. Column short, glabrous, clinandrium obtusely 3-lobulate, the median lobule smaller; column-foot incurved, ligulate. Anther rhomboid-cucullate, glabrous, in front truncate.
(after Schlechter, 1912).
Colours: Flower light yellow, densely spotted red, lip in front white.
Habitat: Epiphyte in lower montane forest. Altitude 900 m.
Flowering time in the wild: September.
Distribution: New Guinea (endemic).
Distribution in New Guinea: Papua New Guinea (Madang Province: Kani Mountains).
Map: EXASPMAP.JPG [Dendrobium exasperatum Schltr., distribution map.]
Cultivation: Intermediate growing epiphyte.