Marsdenia salaschiblii (Apocynaceae: Asclepiadoideae), a new species for the southeast of Oaxaca, Mexico

Abstract

Marsdenia R.Br. (Apocynaceae: Asclepiadoideae, Marsdeniae) is a species-diverse genus of Apocynaceae from Mexico. Here, a new species, Marsdenia salaschiblii, from the state of Oaxaca in southeastern Mexico, is described and illustrated. The morphological features of this new taxon are different from those of known species of Marsdenia in Mexico. It is morphologically similar to M. propinqua Hemsl. and M. veronicae W.D.Stevens, but can be distinguished by a long pedunculated inflorescence, which is an umbellate thyrsoid with (2) 3 – 4 rachides, and gynostegial corona lobes at the level of the anthers or slightly above them. We provide images to distinguish the new species and to aid in its identification, as well as a key to diagnose the species in Oaxaca. In addition, we suggest the conservation status of the new taxon based on the IUCN criteria and we provide a distribution map for the new Marsdenia.