Four new species of Matelea (Apocynaceae: Asclepiadoideae) endemic to Mexico

Summary Four new species of Matelea , endemic to Mexico, are proposed and described: M. balrog, M. cornuta, M. jaimesiae and M. lokii. These taxa differ from each other and M. gonoloboides , M. medusae and M. porphyrantha (the Matelea gonoloboides species complex) in their corolla shapes and gynostegial corona ornamentation. Descriptions, illustrations, morphological comparisons and geographic distributions of these species, as well as their conservation status, are provided. A lectotypification for the name M. gonoloboides is also included . These discoveries highlight Mexico as a centre of diversity and endemism for the genus, with 69 species currently known from the country, of which 66% are restricted to it.