Robust epiphyte. Pseudobulbs cylindrical, to 3 m long, slender, arching or pendent. Leaves numerous, oblong-elliptic, to 18 cm long, to 3 cm wide, soon falling. Flowers 1 or 2, to 10 cm wide, pink to purple with dark purple throat; winter to spring. Sepals lanceolate. Petals ovate, wider than sepals. Labellum ovate, funnel-shaped at base, hairy.
Occasionally cultivated are:
D. signatum Rchb. f., which has white or cream flowers with twisted segments and a yellow labellum sometimes with 2 purplish blotches near the base.
D. tortile Lindl., which is similar to D. signatum but is less robust.
D. moniliforme (L.) Sweet, which has white or pink flowers with a narrow labellum, which is often greenish with brown spots near the base.
SE Asia, the Philippines, Indonesia and New Guinea.
Source: (2005). Orchidaceae. In: . Horticultural Flora of South-eastern Australia. Volume 5. Flowering plants. Monocotyledons. The identification of garden and cultivated plants. University of New South Wales Press.