Shedding light on the controversial taxonomic status of Culicoides jamaicensis and Culicoides paolae (Diptera: Ceratopogonidae): an overseas trip among continents.

Culicoides biting midges (Diptera: Ceratopogonidae) are small bloodsucking flies that act as vectors for various pathogens of medical and veterinary importance. This study aimed to examine, using a comprehensive approach, the controversial taxonomic status of 2 Culicoides species that are currently distributed in the Neotropical (Culicoides jamaicensis Edwards) and Palearctic (Culicoides paolae Boorman) areas and possess unique and distinctive features. Previous investigations based on morphological analysis have suggested that these 2 species may be synonyms. Our work updated the current geographical distribution of both species and analyzed new specimens from different geographic origins, together with publicly available sequences. We used 2 universal genetic markers (COI and 28S) to test this hypothesis. Our study reveals evidence that C. paolae and C. jamaicensis belong to the same species due to the following statements: (i) similar morphological features; (ii) low interspecific genetic variation; (iii) association with a single genetic cluster; (iv) inclusion within the subgenus Drymodesmyia, which has only been recorded in the New World; and (v) occurrence in habitats with moderate temperatures. We recommend that European and African specimens of C. paolae be considered from now on as C. jamaicensis. Our comprehensive approach shed new light on the taxonomic status of these 2 Culicoides species and has implications for future studies on their biology and ecology.