A cryptic new species in the Cyrtorchis ringens complex (Orchidaceae, Angraecinae)

Abstract

Recent morphological and phylogenetic studies highlighted the paraphyly of Cyrtorchis sect. Homocolleticon, in which Cyrtorchis ringens sensu lato constitutes a polyphyletic species complex. In this complex, three morphogroups were distinguished, representing putative new taxa. Here, we describe one of these new taxa based on a morphological and morphometric study of herbarium specimens from western and central tropical Africa (Cameroon and Guinea) taking into account previous phylogenetic results and phytogeographic data. The new species, Cyrtorchis leptophylla, is sister to C. ringens sensu stricto and belongs to the same clade as C. okuensis. It differs from C. ringens s.s. in having narrower, linear or narrowly elliptic leaves and a shorter inflorescence with fewer flowers. It is preliminarily assessed as Vulnerable (VU).