Common name: Tree Spider Orchid
Dendrobium tetragonum A.Cunn. APNI*
Synonyms: Tetrabaculum tetragonum (A.Cunn.) M.A.Clem. & D.L.Jones APNI*
Description: Epiphyte with stems spreading to pendent, thin and wiry in the basal half, succulent, swollen and square in cross section in the upper half, tapering towards apex, rooting only at base, 6–45 cm long, 7–9 mm diam., with 2–5 leaves at apex; roots smooth, creeping.
Leaves spreading to erect, elliptic, 3–8 cm long, 15–25 mm wide, conduplicate, acuminate, thin, smooth.
Inflorescences 0.5–4 cm long, 1–5-flowered. Sepals green to deep dull yellow, usually with reddish margins or other markings; lateral petals green to deep dull yellow; dorsal sepal 19–30 mm long, 2–3 mm wide; labellum cream, usually with reddish striations, 8–10 mm long, 6–8 mm wide. Column 2.5–4 mm long; column foot 5–6 mm long.
Distribution and occurrence: Grows on rainforest trees and along streams; coastal districts, north from the Illawarra region.
NSW subdivisions: NC, CC
Other Australian states: Qld
Text by P. H. Weston
Taxon concept: Flora of NSW 4 (1993)
APNI* Provides a link to the Australian Plant Name Index (hosted by the Australian National Botanic Gardens) for comprehensive bibliographic data
***The AVH map option provides a detailed interactive Australia wide distribution map drawn from collections held by all major Australian herbaria participating in the Australian Virtual Herbarium project.