Phylogeny of subtribe aeridinae (orchidaceae) inferred from DNA sequences data: advanced analyses including australasian genera

Abstract

Advanced phylogenetic analyses of the orchid subtribe Aeridinae has been conducted using DNA sequences of ITS region of nrDNA and matK of cpDNA. In the preliminary work, we only involved the most representative Asian genera of the subtribe. Further, to establish more robust relationships in the Aeridinae, in this study we have extended the sampling to include Australasian specimens. Our analyses revealed that: (1) the subtribe is reorganised by four major groups with 11 subgroups (This is inconsistent with previous classification systems of the subtribe); (2) the Australasian region is a secondary center of diversification of the subtribe; (3) vegetative features have shown to have greater value than reproductive one in determining major groups in the subtribe; and (4) at genus level, some genera, i.e. Phalaenopsis, Cleisostoma, Sarcochilus, and Aerides are shown to be non-monophyletic. This study also resolved the taxonomic status of Aerides flabellata Rolve ex Downie, a species with a debatable generic position.