Revision of the bactrianus subgroup of the genus EumerusMeigen (Diptera: Syrphidae) in Europe, inferred from morphological and molecular data with descriptions of threenew species

摘要

With more than 300 described species, the genus Eumerus is one of the largest genera of hoverfies (Diptera: Syrphidae). In thispaper, we defne the Eumerus bactrianus subgroup and revise the subgroup in Europe for the frst time, providing an illustrated key for itsEuropean species. We describe three new species: E. banaticus Nedeljkovi?, Grkovi? & Vuji? n.sp. from Serbia and Romania; E. bicornisGrkovi?, Vuji? & Hayat n.sp. from Greece and Turkey; and E. bifurcatus van Steenis & Hauser n.sp. from Spain. Species of this subgroupexhibit a distinctive apomorphic morphological feature, i.e. the bifurcated posterior surstylus. We discuss the distributions of seven Palaearctic species of this subgroup: E. bactrianus Stackelberg, 1952, E. pannonicus Ricarte, Vuji? & Radenkovi?, 2016, E. turanicola Stackelberg, 1952, E. turanicus Stackelberg, 1952, and three species described here. Molecular species delimitation, which strongly supports ourmorphological results, is based on maximum parsimony analysis of mitochondrial COI sequences.