New Gonolobus (Apocynaceae, Asclepiadoideae, Gonolobeae, Gonolobineae) for the Trans-Mexican Volcanic Belt, Puebla, Mexico

Background: Field trips were carried out to Puebla, where a climbing plant of Gonolobus was found that did not coincide with the morphologi-cal description of any other species in the genus. Here a new species is proposed and compared with the species G. cuajayote and G. jaliscensis.Questions: Are the Gonolobus plants collected in the Sierra del Tentzo, Puebla, new to science? How do they differ from other species of the genus? What is its distribution and conservation status?Studied species: Gonolobus sp. nov.Study site and dates: Sierra del Tentzo State Park, Puebla State, Mexico. Methods: A description and morphological analysis was carried out based on the material collected. A comparison with related taxa and an identification key was generated following the cohesive species concept. Conservation status was assessed following IUCN criteria.Results: Gonolobus volcanicus is proposed as a new species for Mexico. The species is recognized from other morphologically similar species by the dense pubescence of the corolla and corona, the shape of the dorsal appendages of the anthers, and its distribution. The morphological description of the new species, images of the taxa treated, a map of geographic distribution, and conservation status are provided. A key to the Gonolobus species registered in Puebla is presented, including similar species. Conclusions: Gonolobus volcanicus is recognized as a new species. This discovery increases to 46 the number of Gonolobus species recorded for Mexico, and represents the first endemic Gonolobus to Puebla.