Dendrobium alexandrae

Dendrobium alexandrae Schltr., Repert. Spec. Nov. Regni Veg. Beih. 1 (1912) 493; 21 (1923) t. 168, fig. 624.

Type: Schlechter 19857 (holo B, lost).

A robust epiphytic plant. Pseudobulbs subclavate, longitudinally sulcate, up to 55 by 1-2 cm, 3-4-leaved at apex. Leaves erect-spreading, coriaceous, elliptic, acuminate, 11-16 by 3.5-5.5 cm, bluish-green. Inflorescence subterminal, up to 25 cm long, laxly 3-7-flowered; bracts lanceolate, acute, 3-6 mm long. Flowers large; pedicel and ovary about 1.8 cm long. Dorsal sepal lanceolate, long-acuminate, c. 5 cm long; lateral sepals falcate but similar; mentum broadly conical, obtuse, 1.3 cm long. Petals spreading, obliquely lanceolate, 5 cm long, with conspicuously undulate margins. Lip shortly clawed and cuneate below, 3-lobed, 5 by 3 cm; side-lobes erect, subquadrate, with crenulate margins; midlobe much longer than side-lobes, ovate, long-acuminate, 3.7 by 2 cm; callus 3-ridged above, with an apicule on claw below. Column short, fleshy; foot 1.3 cm long.
(after Cribb, 1983).

Colours: Flowers yellowish, spotted dull red on sepals and petals; lip shining violet with brownish violet spots and venation.

Habitat: Epiphyte on high branches in lower montane forest, in rather exposed positions. Altitude 900 to 1200 m.

Flowering time in the wild: June.

Distribution: New Guinea.

Distribution in New Guinea: Papua New Guinea (Sandaun Province; Morobe Province; Central Province).

Map: ALEXAMAP.JPG [Dendrobium alexandrae Schltr., distribution map, redrawn from P. Cribb, Kew Bull. 38 (1983) 250, map 4, with new records added.]

Notes: Dendrobium alexandrae is a large-flowered species, closely allied to Dendrobium spectabile but differing in its shorter broader lip and in lacking the strongly undulate margins to the lip and sepals.
(after Cribb, 1983).

Cultivation: Intermediate growing epiphyte.