Revisions of the clavipes and pruni species groups of the genus Merodon Meigen, 1803 (Diptera, Syrphidae).

This study focuses on the avidus-nigritarsis lineage within the genus Merodon , exploring morphological, genetic, and distributional aspects of two related assemblies within this lineage: the clavipes and pruni species groups. An integrative taxonomic approach was followed to ensure comprehensive species identification and validation, using adult morphology, wing geometric morphometrics, and genetic analysis of the mtDNA COI gene. In the clavipes group, seven species were identified, including three new species: M.aenigmaticus Vujić, Radenković & Likov, sp. nov. , M.latens Vujić, Radenković & Likov, sp. nov. , and M.rufofemoris Vujić, Radenković & Likov, sp. nov. In the pruni group, our revision revealed a new species, M.aequalis Vujić, Radenković & Likov, sp. nov. , and the revalidation of Merodonobscurus Gil Collado, 1929, stat. rev. Merodonpallidus Macquart, 1842 is redescribed. Diagnoses, identification keys to species, and distribution maps are provided, and neotypes for Syrphusclavipes Fabricius, 1781 and Merodonquadrinotatus (Sack, 1931) are designated. Additionally, the following new synonyms are proposed: M.clavipesalbus syn. nov. , M.clavipesater syn. nov. , M.clavipesniger syn. nov. , and M.splendens syn. nov. are junior synonyms of M.clavipes ; and M.veloxarmeniacus syn. nov. and M.veloxanathema syn. nov. are junior synonyms of M.velox .