Dichopus insignis Blume, Mus. Bot. 2: 176 (1856); Dendrobium insigne (Blume) Rchb.f. ex Miq., Fl. Ind. Bat. 3: 640 (1855); Grastidium insigne(Blume) M.A.Clem. & D.L.Jones, Lasianthera 1(2): 116 (1997). Type: New Guinea, Zippelius s.n. (holo L).
Dendrobium lyperanthiflorum Kraenzl., Ost. Bot. Zurich 44: 333 (1894) & Engl., Plfanzenreich Orch.-Mon.-Dendr. 1: 198, f. 14A-C (1910); Grastidium lyperanthiflorum (Kraenzl.) Rauschert, Feddes Repert. 94(7-8): 450 (1983). Type: New Guinea: New Britain, In the Bay at Port Weber, Dec., Micholitz s.n. (holo HBG).
Dendrobium pentactis Kraenzl. in Engler, Pflanzenreich Orch.-Mon.-Dendr. 1: 200 (1910). Type: Papuanische Provinz: Aru-Inseln, Beccari s.n. (holo FI).
Dichopus insignis var. subsimplex J.J.Sm., Nova Guinea 8(1): 564-65, t. 92B (1911). Type: cult. Batavia ex Nijman, Frau M. Vietor Sibinga (holo BO).
Occurs in territorial Queensland on Saibai Island, which lies in the Torres Strait, 4 km off the coast of Papua New Guinea.
Altitude: 1-10 m.
Also occurs in Bougainville, Indonesia and New Guinea.
Epiphytic or lithophytic herb forming large straggly clumps. Stems crowded, erect to arching, slender, cane-like, 30-100 cm x 0.4-0.5 cm, flattened, often shedding leaves from the apical part. Leaves numerous, scattered along stem, largest in middle of stem, prostrate, alternate, distichous, sessile; lamina oblong to ovate, 4-7 cm x 1-3 cm, dark green, fleshy, apex unequally emarginate. Inflorescence an axillary raceme, emerging opposite a leaf, flowers usually in pairs; peduncle short, to 10 mm long; pedicels 7 mm long. Flowers in groups of 2-3, resupinate, porrect, star-shaped, 25-35 mm x 25-35 mm, yellow with orange or red markings and white labellum, fragrant, short-lived. Sepals and petals widely spreading to incurved, somewhat fleshy. Dorsal sepal erect, oblong, 15-20 mm x 5 mm, bases fused to column foot, apex incurved, acuminate. Lateral sepals widely divergent, more or less triangular, falcate, 15-20 mm x 7-9 mm. Petals incurved, lanceolate, 14-17 mm x 4 mm. Labellum 18 mm x 8 mm, white, 3-lobed; lateral lobes very small, apiculate; midlobe sharply decurved, with 2 hairy ridges, each ridge with 3-5 long narrow projections. Column 4 mm long. Column foot 6-7 mm long, nearly at right-angles to column. Capsules pendulous, dehiscent.
Occurs in mangroves and is known from a single Australian collection. In New Guinea it commonly occurs in lowland rainforests. The stems continue growing for many years, becoming longer with age, and the apical leaves are small compared to the leaves below. Flowers are produced sporadically from nodes along the length of the stem, and are strongly fragrant, lasting less than 2 days.
Flowering period: Sporadic throughout the year.
Until recently known as both Dendrobium insigne and Grastidium insigne.