Dendrobium canaliculatum

Dendrobium canaliculatum R.Br., Prodr. (1810) 333.

Type: Illust. Banks s.n. (Tropical Australia) (acc. to Cribb: R. Brown s.n.) (holo BM).

A small epiphytic herb. Stems usually pseudobulbous, fusiform to ovoid, few-noded, 3-12 cm long, 1.5-3 cm diam., clothed at first in sheathing bracts. Leaves 2-6, subterminal, semi-cylindrical, grooved on upper surface, linear, acute, 5-20 by 1.2-1.6 cm, articulated on base to a very short sheath. Inflorescences 1-4, 10-40 cm long, densely many-flowered; bracts lanceolate, acuminate, 3-4 mm long. Flowers small, 1.8-2.5 cm across, fragrant; pedicel and ovary 1.2-2.5 cm long. Dorsal sepal oblong, acute to obtuse, 0.9-1.5 by 0.3-0.4 cm, once-twisted; lateral sepals spreading, obliquely oblong, acute, 0.7-1.5 by 0.3-0.4 cm, twisted; mentum 0.5 cm long. Petals suberect, linear to spathulate, obtuse to acute, 1.2-1.8 by 0.2-0.3 cm, not twisted to twice-twisted. Lip 3-lobed, 0.9-1.5 by 0.8-0.9 cm; side-lobes obovate, rounded or truncate at apex; midlobe sometimes recurved, ovate, acute or apiculate; callus of 3 to 5 ridges dissected towards apex, middle three raised at apex. Column 3-4 mm long.
(after Cribb, 1986).

Colours: Sepals and petals white with yellow to brown apical halves, sometimes yellow or brown; lip white marked on lobes with purple.

Habitat: Epiphyte in savannah, often fully exposed on Melaleuca trees; sea-level to 500 m.

Distribution: North eastern tropical Australia and South New Guinea.

Map: CANALMAP.JPG [Dendrobium canaliculatum R.Br., distribution map, redrawn from P. Cribb, Kew Bull. 41 (1986) 629, map 2.]

Notes: This distinctive orchid is readily recognised by its ovoid or shortly fusiform pseudobulbs, semiterete leaves grooved on the upper surface and dense racemes of small flowers, 18-25 mm across, with a straight mentum at a right angle to the ovary and a lip in which the callus ridges are raised on the midlobe. Its only close ally is Dendrobium carronii, which has quite different flowers and a more restricted distribution.
(after Cribb, 1986).

Cultivation: Warm growing epiphyte, prefers light position.