DNA barcoding of Afrotropical nose flies (Diptera, Calliphoridae, Rhiniinae): species identification, female-male...

DNA barcoding offers a practical approach to species identification, especially in morphologically complex taxa such as Rhiniinae (Diptera, Calliphoridae). The most extensive COI barcode dataset for the subfamily to date was assembled, combining 216 newly generated sequences with more than 1,150 publicly available records from BOLD Systems and GenBank, with emphasis on Afrotropical taxa. Distance-based analyses, Neighbour-Joining (NJ) and Maximum Likelihood (ML) clustering, were evaluated, as well as automated barcode clustering approaches (ABGD and ASAP), for identifying morphospecies within this group. These analyses recognized 79 putative Afrotropical species, with most morphospecies forming well-supported barcode clusters congruent with morphological identifications. Several lineages, however, including species of Fainia, Rhinia, Cosmina, Stomorhina, and Rhyncomya, displayed low interspecific COI divergence, indicating that COI alone offers limited resolution. Yet, NJ and ML clustering helped highlight problematic taxa and identify previously unrecognized lineages. Public data on BOLD Systems comprised 957 BINs identified to subfamily level. Integrating ML, ABGD, ASAP, and voucher-based assessment allowed the assignment of 749 unnamed BINs to 11 species names, 193 BINs to eight genus names within 24 morphospecies, 12 BINs remain as Rhiniinae, and three represent non-Rhiniinae. The analyses also allowed linking 31 Afrotropical female morphotypes to their conspecific male morphotypes. This study establishes the first quality-controlled COI reference library for Afrotropical Rhiniinae and provides a framework for future taxonomic, ecological, and molecular investigations.