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Synonyms: Thelychiton Endl. APNI*
Australorchis Brieger APNI*
Tetrabaculum M.A.Clem. & D.L.Jones APNI*
Tropilis Raf. APNI*
Dockrillia Brieger APNI*
Aporopsis (Schltr.) M.A.Clem. & D.L.Jones APNI*
Cepobaculum M.A.Clem. & D.L.Jones APNI*
Ceratobium (Lindl.) M.A.Clem. & D.L.Jones APNI*
Coelandria Fitzg. APNI*
Davejonesia M.A.Clem. APNI*
Dichopus Blume APNI*
Durabaculum M.A.Clem. & D.L.Jones APNI*
Eleutheroglossum (Schltr.) M.A.Clem. & D.L.Jones APNI*
Grastidium Blume APNI*
Trachyrhizum (Schltr.) Brieger APNI*
Vappodes M.A.Clem. & D.L.Jones APNI*
Stilbophyllum D.L.Jones & M.A.Clem. APNI*
Monanthos (Schltr.) Brieger APNI*
Leioanthum M.A.Clem. & D.L.Jones APNI*
Ceraia Lour. APNI*

Description: Epiphytic, epilithic or rarely terrestrial herbs, sympodial; roots creeping over the surface of the substrate or aerial or rarely subterranean, usually fibrous. Stems slender and undifferentiated or differentiated into rhizome and pseudobulb; pseudobulb of several to many internodes, usually cane-like.

Leaves tufted at apex of shoot or apparently terminal [or scattered along the pseudobulb], 1–6 [or many] per shoot, distichous, conduplicate or flattened or terete [or laterally flattened].

Inflorescence racemose, 1–many-flowered, lateral but often subterminal or apparently terminal; flowers resupinate or not. Dorsal sepal free, similar to lateral sepals. Lateral sepals united basally to each other and to column foot forming a mentum, otherwise free. Lateral petals free, usually slightly smaller [or larger] than dorsal sepal. Labellum free, hinged to the tip of the column foot; lamina obscurely to distinctly 3-lobed, usually bearing 1–7 longitudinal keels. Column lacking free filament and style; column wings fused to column, reduced to teeth that project beside the anther. Column foot usually as long as or longer than the column itself. Anther incumbent, cap-like. Pollinia 4, waxy. Stigma entire. Rostellum not prominent, ventral.

Illustration Unknown

Distribution and occurrence: World: c. 1400 spp., Asia (as far west as India and as far north as Korea), Melanesia, Aust. & N.Z. Aust.: 71 spp. (52 spp. endemic), all States except S.A.

Molecular phylogenetic analyses (e.g. Yukawa et al. 2000, pp. 465-471 in Monocots: Systematics and Evolution; Clements 2003, Telopea 10: 247-298) resolve genera traditionally allied with Dendrobium, including Cadetia, Dockrillia, Epigenium and Flinkringia nested within Dendrobium. The two alternative solutions to this problem of Dendrobium paraphyly have both been proposed in the last couple of decades, one proposal is to retain a broadly circumscribed Dendrobium by including these segregate genera, the other to subdivide Dendrobium to retain the segregates. To date, proposals to subdivide Dendrobium have not been without problems of their own, and have not been widely adopted as a result. The National Herbarium of New South Wales accepts a broadly circumscribed Dendrobium, including Dockrilla and other segregates.

Several Australian species, including D. speciosum, D. striolatum, D. teretifolium and D. tetragonum exhibit morphological variation, which may be ecologically and/or geographically structured. In each of these species complexes, variation has been subject to different interpretations, with components being recognised as separate taxa, at species rank in some proposed classifications or as sub-species or varieties in others. To date, data allowing an empirical assessment of the observed variation has only been presented for D. speciosum, and supports the interpretation of this complex as a single species that expresses geographically structured morphological variation. For the other species complexes, while there is no doubt that differences among individuals exist in each case, whether those differences reflect separate species status has not been addressed empirically. Therefore, we adopt a conservative stance on species circumscription, which follows established precident and generally recognises morphotypes in New South Wales as varieties. Publication of empirical evidence supporting separate species status for these varieties will result in their being recognised as such.