Reconsideration of the taxonomic status of Bulbophyllum obtusangulum (Orchidaceae) from southern China

Bulbophyllum obtusangulum Z.H. Tsi has long been treated as a synonymy of B. lepidum (Blume) J.J. Sm., which is broadly distributed in Southeast Asia. In this paper, based on a re-evaluation of morphological characters and critical study of herbarium specimens and protologue, B. obtusangulum is proposed as a heterotypic synonym of B. tseanum (S.Y. Hu & Barretto) Z.H. Tsi, which was previously regarded as endemic to Hong Kong.