Integrated taxonomic revision of Afrotropical Xyleborinus reveals an extraordinary recent radiation on Madagascar

Abstract

Collection efforts on Madagascar have previously revealed a high species diversity in the Scolytinae genus Xyleborinus Reitter, 1913 compared with the African mainland. This study has produced a well supported phylogeny based on gene fragments of COI, 28S and CAD revealing that the genus colonized Madagascar once as recently as 8.5-11.0 Ma, indicating an extraordinary recent radiation on the island that has given rise to at least 32 species. Two recolonization events back to the African mainland are also proven, with several more being indicated. A taxonomic re-evaluation of Afrotropical Xyleborinus has been conducted, resulting in a revision of the genus in the Afrotropic. Eleven species from Madagascar are described as new to science, six species names are synonymized, two species names are given new status and two species are removed from the genus. An updated species register of Xyleborinus in the Afrotropic based on morphology and molecular data, when available, is included. Register includes diagnostic characters and photographs of all 46 described species. The first identification key for the group is also included.