Notes on Inflorescence Structure of Boesenbergia (Zingiberaceae)

摘要

One-sided spiral arrangement of bracts is described in detail with comparison of distichous one in Boesenbergia (Zingiberaceae). Association among inflorescence structure, anther dehiscence patterns, and geographic distribution are discussed. Boesenbergia O. Kuntze is a relatively large genus in the Zingiberaceae currently including about 80 species. Recent publications describing many new species (Smith 1987, Poulsen 1993, Larsen 1993, 1997, Cowley 1998, 2000, Saensouk & Larsen 2001, Sakai & Nagamasu 2006) indicate that others are yet to be described. Boesenbergia has been regarded as a well-defined genus characterized by the two-ranked (distichous) arrangement of the bracts and an inflorescence in which flowers open from the apex to the base (determinate). Within the family, these characteristic are known only in the closely related Haplochorema and probably in the more distantly related Caulokaempferia. Boesenbergia differs from those two genera in its concave labellum and small anther crest (Larsen & Smith 1972, Smith 1987).