paper title

Phylogenetic relationships in the Pterygiella complex (Orobanchaceae) inferred from molecular and morphological evidence.

Author

 Dong LN, Wang H, Wortley, AH, Lu L, Li DZ.

Published journals

 Botanical Journal of the Linnean Society

Year/Journal/Paper

 2013/171/491-504

Abstract

The Pterygiella Complex, i.e. Pterygiella,Phtheirospermum, Pseudobartsia and Xizangia, is controversial in terms of both its relationships and taxonomic status. The genera of the complex are all species-poor and endemic to eastern Asia. In this study, we sampled all taxa within the complex for seven genic regions (atpB-rbcL, atpH-I, psbA-trnH, rpl16 intron, trnL-F, trnS-G and ITS), which were analysed separately and in combination. We examined capsule and seed morphology of these genera by scanning electron microscopy (SEM). Our results indicate that the complex is a polyphyletic group comprising two distinct clades. The first clade, designated “Pterygiella Complex I”, includes only Phtheirospermum japonicum. This clade is uniquely diagnosed by its papery yellow capsule and reticulate secondary thickening on the seed coat. The second clade, “Pterygiella Complex II”, includes Phtheirospermum tenuisectum, Phtheirospermum parishii, Phtheirospermum muliense,Psuedobartsia, Xizangia and Pterygiella. These taxa share a coriaceous capsule. Pterygiella itself is a monophyletic group characterized by eglandular, unicellular, pilose hairs on the capsule and hook-like protuberances on the horizontal ridges of the striate or reticulate seed coat. ExcludingPhtheirospermum japonicum, the remaining taxa in Phtheirospermum cluster together and are sister to Pterygiella. Xizangia bartschioides and Pseudobartsia yunnanensis are separated from Pterygiella and Phtheirospermum respectively, and are supported as genera by both molecular and morphological evidence.