Dendrobium section Phalaenanthe Schltr.,
Repert. Spec. Nov. Regni Veg. Beih. 1 (1912) 447.
Rhizome short. Pseudobulbs elongated, with many internodes, rather fleshy, several-leaved in apical part. Leaves sheathing at the base, glabrous, usually coriaceous. Inflorescences lateral from the upper part of the stem, or subterminal, racemose, few- to many-flowered. Flowers medium-sized to rather large, resupinate, long-lived, showy. Petals much broader than the sepals. Mentum with a bulge in front and with a spur-like apical part. Lip not mobile.
Lesser Sunda Islands, Moluccas, New Guinea, Australia. Three species, all occurring in New Guinea, of which one is endemic (Dendrobium williamsianum Rchb.f.).
Epiphytes in lowland forest and savannahs, in areas with a distinct dry season.
From an economical point of view, this section is perhaps the most significant of the whole genus. That is because one of its members, Dendrobium bigibbum, gave rise to numerous hybrids on which an enormous cut-flower industry depends. Most of these hybrids, however, involve selected forms of D. bigibbum called Dendrobium phalaenopsis, which do not occur in New Guinea. As a matter of fact, the distribution of Dendrobium bigibbum in New Guinea is very imperfectly known: we are not aware of any precise localities where a thriving population can be found. The two other species of this section, while attractive enough, are relatively unimportant horticulturally. Section Phalaenanthe is undoubtedly closely related to section Spatulata, with which it hybridises easily, even in the wild. A good case could be made for uniting these sections.