Gomphichis contains about 23 species of terrestrial orchids. The genus has a continuous distribution from Costa Rica to Bolivia with disjunct species in the Guayana Highlands and southeastern Brazil. Gomphichis and its close relatives Aa, Altensteinia, Myrosmodes, Porphyrostachys, Prescottia and Stenoptera have been placed within the subtribe Prescottiinae, tribe Cranichideae (Dressler, 1993). The Prescottiinae include most of the Neotropical terrestrial orchids that flourish at high and middle elevations in the major mountain chains of Central and South America. Phylogenetic relationships within the subtribe Prescottiinae are unclear and generic limits among some of their members are questionable. In order to provide the first phylogenetic hypothesis for Gomphichis and the Prescottiinae, we generated a molecular phylogeny based on ITS sequence data. Ingroup taxa included most members of the Prescottiinae, except Stenoptera. Outgroup taxa consisted of representatives from three of six subtribes currently recognized in Cranichideae. Preliminary analyses support the monophyly of Gomphichis and suggest the paraphyly of the Prescottiinae (sensu Dressler, 1993). Further molecular and morphological studies are underway to circumscribe Gomphichis and define an expanded concept of the subtribe Prescottiinae.

Key words: Gomphichis, ITS, Neotropics, Orchidaceae, Phylogeny, Prescottiinae