From the Latin imbricatus (overlapping like roofing-tiles/shingles), referring to 2 rows of large bracts which subtend the flowers.

Rattlesnake Orchid.

Pseudobulbs crowded, 80–120 × 30–50 mm, smooth or furrowed, grey-green. Leaf on a stalk c. 50 mm long, 200–400 × 60–80 mm, dark green, plicate, thick. Racemes 150–400 mm long, wiry, base erect, flower-bearing part pendulous, 20–60-flowered. Flowers closely packed in 2 crowded rows, cupped, 6–8 × 5–7 mm, white, greenish or cream, each flower subtended by a large, pinkish, concave bract. Dorsal sepal 4–5 × 3–4 mm. Lateral sepals 6–7 × 3 mm. Petals 3–4 × 1.5 mm. Labellum deeply concave, c. 4 × 5 mm, 3-lobed; lateral lobes large, erect, blunt; midlobe also 3-lobed.

Coarse epiphyte with crowded, cylindrical pseudobulbs, each with single, large, leathery, pleated leaf; and arching, wiry racemes with a pendulous section of flowers and bracts arranged in 2 crowded rows.

Flowers March–May.

Native.

N.T. (N), Qld (Moa Island, Dauan Island, Cape York to Townsville); 5–900 m altitude; also occurs in New Guinea, Indonesia, Malaysia, South East Asia and southern China.

Widespread and common; found growing on trees and rocks in rainforest, rainforest margins and moist, humid areas in wetter open forests; occasionally on mangroves.

Named Pholidota imbricata in 1825 by William Jackson Hooker based on a plant cultivated at the Royal Botanic Gardens, Kew, England, and originally collected by Nathaniel Wallich from an undisclosed locality (probably not an Australian locality). Although placed in Coelogyne in 1861, this species has commonly been included in the genus Pholidota, however the results of a detailed morphological study of Coelogyne places Pholidota within Coelogyne (Gravendeel et al. 2001).

[This taxon is treated as Pholidota imbricata Hook. by the Australian Plant Census (CHAH 2018, accessed December 2022); this name is treated as nomenclatural synonym of Coelogyne imbricata (Hook.) Rchb.f. by the Royal Botanic Gardens, Kew (see Coelogyne imbricata in Plants of the World Online). - Editor 16 December 2022.]

The author counted 38 capsules formed from 44 flowers (about 86% success rate) on spikes of this orchid at FM Hill on Cape York Peninsula on 7 September 1976.

D.L. Jones, A Complete Guide to Native Orchids of Australia 3rd edn: 744 (2021).

Gravendeel, B., Chase, M.W., De Vogel, E.F., Roos, M.C., Mes, T.H.M. & Bachmann, K. (2001). Molecular phylogeny of Coelogyne (Epidendroideae: Orchidaceae) based on plastid RFLPS, MATatK, and nuclear ribosomal ITSits sequences: evidence for polyphyly. American Journal of Botany 88(10): 1915–1927.

Jones, D.L. (2021). A Complete Guide to Native Orchids of Australia 3rd edn. (Reed New Holland: Sydney).

Royal Botanic Gardens, Kew. Coelogyne imbricata in Plants of the World Online [accessed 16 December 2022].

Published 16 December 2022. This profile has been adapted from A Complete Guide to Native Orchids of Australia 3^rd edn (2021) by D.L. Jones. The online Flora of Australia Orchidaceae project was made possible with support from the Australian Orchid Foundation and the Australian Biological Resources Study.