Thelychiton × ruppiosus (Clemesha) M.A.Clem. & D.L.Jones, Orchadian 13(11): 492 (2002).
Dendrobium × ruppiosum Clemesha, Orchadian 7(4): 91-2 (1982). Type: cult. Woolgoolga, Sep. 1981 ex In the mountains near Tinaroo Dam north Queensland, Jan. 1964, S.C. Clemesha s.n. (holo BRI).
Occurs in north-eastern Queensland from the Atherton Tableland to Tully Falls.
Altitude: 600-900 m.
Epiphytic or lithophytic herb forming thick, medium-sized clumps. Pseudobulbs erect, fusiform, 25-35 cm x 4-5 cm, green to yellowish, ribbed. Leaves 2-4, apical, erect to prostrate, distichous, alternate, sessile, bases sheathing pseudobulb; lamina oblong to ovate, 9-15 cm x 3-4 cm, dark green, thin, leathery, apex acuminate. Inflorescence a terminal raceme, 300-400 mm long. Flowers numerous, resupinate, porrect, star-shaped, 25-30 mm x 30-40 mm, white to cream. Sepals and petals widely spreading, moderately narrow. Dorsal sepal obliquely erect, narrowly triangular, 25-35 mm x 4-5 mm, apex obtuse. Lateral sepals divergent, narrowly triangular, falcate, 25-35 mm x 4-5 mm, bases fused to column foot. Petals linear, 20-30 mm x 2-3 mm, apex acute. Labellum 10 mm x 8 mm, white with purple markings, 3-lobed; lateral lobes crescent-shaped; midlobe short, with single orange ridge, apex truncate, with short central point. Column broad, tapering toward apex, 7 mm long. Column foot curved, 4 mm long. Capsule pendulous, dehiscent.
Plants are rare and appear to be a natural hybrid between either Thelychiton rupicola or Thelychiton curvicaulis from the Atherton Tableland and Thelychiton jonesii subsp. jonesii. The flowers are strongly scented.
Flowering period: October-December.
Until recently known as Dendrobium × ruppiosum.