Revision of the Merodon bombiformis group (Diptera: Syrphidae) – rare and endemic African hoverflies

In the present work, the Afrotropical species of the bombiformis species group, part of the aureus lineage, are revised. Six species are recognized, based on a combination of morphological and genetic features. Three of these species are new to science: Merodon lotus Vujic & Radenkovic sp. nov., M. vittatus Vujic & Likov sp. nov., and M. zebra Vujic & Radenkovic sp. nov. Redescriptions are provided for the other three species: M. bombiformis Hull, 1944, M. multifasciatus Curran, 1939, and M. nasicus Bezzi, 1915. The female of M. bombiformis is described. The name Merodon edentulus Macquart, 1855 is considered here as a nomen dubium. One new synonymy is proposed: M. apimima Hull, 1944 syn. nov. (junior synonym of M. multifasciatus). The distribution of the bombiformis species group is discussed. The larval host plant of M. multifasciatus is identified as Gladiolus. A key to the identification of both males and females of the bombiformis group is provided.