Oxystophyllum Blume, Bijdr. (1825) 335
- Dendrobium sect. Oxystophyllum ( Blume) Miq., Fl. lnd. Neerl. Bat. 3 (1855) 644. Type species: Dendrobium rigidum (Blume) Miq. non R.Br. (= Dendrobium concinnum Miq.).
- Dendrobium subgen. Aporum (Blume) Kränzl. sect. Holophylla Kränzl. in Engl, Pflanzenr. Orch. Mon. Dendr. 1 (1910) 203 p.p. Type species: not designated.
- Aporum Blume sect. Oxystophyllum (Bl ume) Brieger in Schlechter, Die Orchideen ed. 3, 1 (1981) 676. Type species: Aporum rigidum (Blume) Brieger, nom inval.
Epiphytes or lithophytes, erect or pendant. Roots brown, wiry, very thin. Rhizome short. Stems short to much elongated, slender, branched or not, not fleshy, densely many-leaved throughout, entirely covered by leaf sheaths. Leaves sheathing at the base, overlapping, glabrous, thick coriaceous, bilaterally flattened, with sharp edges and sharp pointed apex; leaf sheaths articulate with the leaf blade. Inflorescences terminal or laterally from the stem, very short, 1-flowered, often in small clusters. Flowers lasting at least several days, small, not opening widely, often rather fleshy, usually dark maroon, sometimes greenish or yellowish. Median sepal free, rigid. Lateral sepals obliquely triangular; mentum well-developed, not tubular in apical part. Petals free, smaller than the sepals. Lip not mobile, fleshy, entire, saccate at the base; at the apex on the abaxial side with a pointed swelling; secreting sticky liquid at the base and along the grooved upper surface. Columm shorter than the column foot; pollinia four, in pairs, attached to prominent caudicles.