Comparative morphology of female terminalia of Calliopum Strand, 1928, Lauxania Latreille, 1804 (Diptera, Lauxaniidae) and allies

The relationships among lauxaniid genera Calliopum Strand, 1928, Lauxania Latreille, 1804 and related species from genus Sapromyza Fallen, 1820 are not fully understood. In this work, we provide a detailed morphological study of terminalia of selected species along with Bayesian phylogenetical analysis of DNA sequences of 4 gene fragments (16 S rRNA, 28 S rRNA, EF1-alpha and COI). Females of Calliopum have a characteristic structure of their terminalia with the exception of C. geniculatum (Fabricius,1805), which is almost identical to L. siciliana Merz, 2001 and L. bilobata Merz, 2001. Female terminalia of L. cylindricornis are rigid and fairly complex, in L. minor Martinek, 1974 they are simple and rigid and in L. albomaculata Strobl, 1909 they are membranous and retractable. In phylogenetic analysis, L. cylindricornis (Fabricius, 1794) clusters with Calliopum with high support. Lauxania minor appears to be sister to Sapromyza columbi Frey, 1936, an endemic species to the Canary Islands, however, support is very weak. Lauxania albomaculata clusters with S. schnabli Papp, 1987 with low support. S. madeirensis Frey, 1949, endemic to Madeira, falls well within Minettia fasciata species group. Our results support the non-monophyly of Lauxania, with the subgenera Callixania Papp, 1978 and Czernushka Shatalkin, 2000 being divergent in terms of DNA sequences from Lauxania s. str. The affinities of Calliopum geniculatum remain equivocal, yet seem to be closer to Lauxania s. str. Suggested systematic changes: Czernushka albomaculata (Strobl, 1909) comb. n, Callixania minor (Martinek,1974) comb. n, Callixania martineki (Shatalkin, 1999) comb. n, Minettia madeirensis (Frey, 1949) comb. n.