The phylogeny and evolution of the Pterygodium-Corycium complex ( Coryciinae, Orchidaceae).

The leaf-anatomy, palynology, seed-morphology, vegetative morphology and especially the highly complicated floral morphology of the Coryciinae s. str. ( Diseae: Orchidoideae: Orchidaceae) are described and illustrated in detail. On the basis of these characters the presumed phylogeny, based on a rigorous cladistic analysis, is presented. The cladistic biogeographical analysis of the Coryciinae s. str. shows that it is a member of the Afrotemperate Track, with a pattern of vicariance events typical of the members of this track. An analysis of the patterns of speciation shows that allopatric speciation appears to be rare, and that parapatric speciation across edaphic boundaries may be the most important factor. Proceeding from the information presented, a new classification of the group is proposed in which we recognize the four genera Ceratandra, Evotella, Pterygodium and Corycium. The new monotypic genus Evotella comprises a species originally described as Pterygodium rubiginosum. The three species of the genus Anochilus are transferred to Corycium and Pterygodium. P. magnum, which was originally described as Pterygodium but was transferred to Corycium lately, is placed in a monotypic section of Pterygodium. [ABSTRACT FROM AUTHOR]