Epipytes or lithophytes with prominent thick branched rhizomes/stems, either appressed to the host and creeping, with coarse roots arising from the nodes, or the plants anchored by coarse roots that arise from basal nodes and with arching to pendulous rhizomes/stems. Pseudobulbs absent but immediately below the base of a leaf is a specialised stem area from which inflorescences and new growths arise. Leaves arranged alternately along the rhizomes/stems, thick, fleshy, without any channel or groove, ranging from crowded to widely spaced and as wide as long to much longer than wide (a significant number are cylindrical-terete). Racemes from a node on the specialised stem area below a leaf. Flowers lasting several days, relatively large, often fragrant. Lateral sepal bases fused with the column foot. Petals narrower than the sepals. Labellum stiffly hinged to the apex of the column foot. Labellum lamina three-lobed, thin-textured.
Significant Generic Characters
Epipytic/lithophytic orchids; rhizomes/stems either creeping and appressed with roots from the nodes or arching to pendulous with roots from basal nodes only; pseudobulbs absent; specialised stem area from which inflorescences and new growths arise occurs just below a leaf; leaves lasting several seasons, alternate, thick, fleshy, ranging from as wide as long to much longer than wide (a significant number are cylindrical-terete); racemes few-many-flowered; flowers lasting several days; lateral sepal bases fused with the column foot; petals narrower than the sepals; labellum stiffly hinged to the apex of the column foot; lamina three-lobed, thin-textured.
Size and Distribution
A genus of about 28 species distributed in Australia, New Guinea, New Caledonia, Vanuatu, Fiji, Samoa and Tahiti. Sixteen species occur in Australia, the majority in Queensland, south from Cape York (10°41' S), and New South Wales, with a single species in Victoria, extending south to near Coles Bay in eastern Tasmania (42°20' S). State occurrence: Queensland (including Moa Island), New South Wales, Victoria, Tasmania.
The native species of Dockrillia are distributed from the coast to the ranges and tablelands to about 1200 m alt. They occur on trees and rocks in a wide range of habitats, including rainforest, swamp forest, open forest and woodland, usually in moist or humid situations but sometimes quite exposed. Some species also favour large boulders and sheltered gorges.
Seasonal Growth: The plants grow actively during the spring and summer months and are relatively quiescent for the remainder of the year.
Hybrids: Natural hybrids involving species of Dockrillia are unknown.
Dockrillia is named after Alick W. Dockrill, contemporary Australian botanist specialising in Australian Orchidaceae.
Perennial, evergreen, epiphytic or lithophytic herbs, sympodial. Plants glabrous. Roots coarse, produced from nodes along the rhizomes/stems. Rhizomes/stems either creeping and closely appressed to the host with roots arising from most nodes or arching to pendulous with roots from the basal nodes and occasional aerial roots, wiry, ageing yellow, branched, when young covered by closely sheathing, imbricate, scarious bracts. Pseudobulbs absent. Trichomes absent. Leaves sessile, not sheathing at the base, ranging from as wide as long to much longer than wide, often terete, not grooved or channelled, thick and fleshy, coriaceous, smooth, pustulate, verrucose or wrinkled; apex entire. Inflorescence racemose, arising from nodes on a specialised stem -section at the base of a leaf, multiflowered (rarely 1-flowered). Peduncle longer than the pedicel, erect, the base covered with tubular scarious bracts. Floral bracts minute, scarious, barely sheathing the base of the pedicel. Pedicels articulate with the rachis, filiform, merging with the ovary. Ovary short, straight, smooth. Flowers resupinate, stalked, lasting 3-10 days, white, cream, greenish or yellowish, often fragrant. Perianth segments thin-textured, spreading. Dorsal sepal free, subsimilar to the lateral sepals; apex entire, flat. Lateral sepals subsimilar to the dorsal sepal, attached by their bases to the column foot; apex entire. Petals free, about as long as the sepals, but narrower; apex entire. Labellum hinged to the apex of the column foot, markedly dissimilar in size and shape to the sepals and petals, ecalcarate. Labellum lamina thin-textured, three-lobed; lateral lobes erect; mid-lobe short to elongated; apex blunt or often caudate and recurved or coiled. Spur absent. Callus with prominent ridges, sometimes wavy. Nectar absent. Column lacking free filament and style, short, nearly straight. Column wings barely discernible, with short tooth-like apical stelidia. Column foot well developed, straight. Pseudospur absent. Anther terminal, incumbent, 2-celled, persistent, attached dorsally by a ligulate claw, smooth or papillate, erostrate or with a short fringed rostrum. Pollinarium absent. Pollinia 4 in 2 pairs, falcate, yellow or orange, hard, waxy. Viscidium absent. Rostellum ventral, transverse. Stigma entire, vertical, concave. Capsules dehiscent, glabrous, pendulous; peduncle not elongated in fruit; pedicel not elongated in fruit. Seeds numerous, light coloured, winged.
Dockrillia is a relatively recent segregate from Dendrobium (Brieger 1981).
Dockrillia Brieger, Die Orchideen 1(11-12): 745 (1981); Dendrobium section Rhizobium Lindl., J. Linn. Soc. 3: 2 (1859). Type species: Dendrobium linguiforme Sw. [Dockrillia linguiformis (Sw.) Brieger].
Banks, D.P. (1996). The genus Dockrillia, the pros and cons. Orchadian 12(2): 61.
Brieger, F.G. (1981). Subtribus Dendrobiinae. In F.G. Brieger, R. Maatsch and K. Senghas (eds), Rudolph Schlechter, Die Orchideen: ihre Bescreibung, Kultur und Züchtung, 3rd edn, Band 1, Teil A, Lieferung 11-12 (Paul Parey: Berlin and Hamburg).
Clements, M.A. & Jones, D.L. (1996). A checklist of the genus Dockrillia. Orchadian 12(2): 60.
Clements, M.A. and Jones, D.L. (2002). Nomenclatural changes in the Dendrobieae (Orchidaceae). 1: The Australasian Region. Orchadian 13(11): 485-492.
Dockrill, A.W. (1969). Australian Indigenous Orchids. Volume 1. The Society for Growing Australian Plants, Halstead Press, Sydney.
Dockrill, A.W. (1992). Australian Indigenous Orchids. Volume 1 & 2. Surrey Beatty & Sons in association with The Society for Growing Australian Plants, Chipping Norton, NSW.
Schlechter, R. (1982). The Orchidaceae of German New Guinea (English translation by R.S. Rogers, H.J. Katz and J.T. Simmons). Australian Orchid Foundation, Melbourne.