Cyrtostachys  

Caespitose or solitary, monoecious palm trees. Stem often conspicuously ringed by leaf scars and with numerous adventitious roots at the base. Leaves reduplicate, pinnately divided; leaf sheath tubular forming a distinct crownshaft, neatly abscising; petiole usually short, pinnae single-fold, regularly arranged. Inflorescence infrafoliar, branched to 2–4 orders, enclosed in prophyll until leaf fall, peduncle short, peduncular bract incompletely enclosing the inflorescence, rachis longer than petiole, first order branches robust spreading, rachillae numerous, throughout with spirally arranged, floral triads of one female flower and two male flowers, these sunken in shallow pits, partly covered by shallow triangular rachillae bracts. Male flowers with petals twice as long as sepals and united basally to c. 1/3 of their length, stamens 8–15, connate at the base; female flowers about the same size or slightly larger, petals slightly larger than than sepals, staminodal ring membranous and reduced, gynoecium unilocular, ellipsoidal with with three sessile, recurved stigmas. Fruit ellipsoidal to sickle-shaped, often black at maturity with persistent perianth basally and apical stigmatic remains, epicarp smooth, mesocarp thin, endocarp poorly differentiated. Seed with homogeneous endosperm.

Seven species in Peninsular Thailand to Papuasia. One species in Thailand.