Integrative taxonomy of Central European Planetella (Diptera: Cecidomyiidae) indicates high species diversity, intraspecific variation and low host specificity

A first attempt is made to revise the European species of the gall midge genus Planetella Westwood, 1840 (Diptera: Cecidomyiidae), with a focus on the fauna of the Czech Republic, Slovakia and Denmark. A total of 19 species are recognized based on unique DNA sequences, of which 13 are described as new to science: Planetella adami Sevcik & Hippa sp. nov., P. aestivalis Sevcik & Hippa sp. nov., P. antennata Sevcik & Hippa sp. nov., P. atrobrunnea Sevcik & Hippa sp. nov., P. attilai Sevcik & Hippa sp. nov., P. csabai Sevcik & Hippa sp. nov., P. davidi Sevcik & Hippa sp. nov., P. galiciensis Sevcik & Hippa sp. nov., P. hlisnikovskyi Sevcik & Hippa sp. nov., P. muranica Sevcik & Hippa sp. nov., P. riparia Sevcik & Hippa sp. nov., P. submontana Sevcik & Hippa sp. nov., and P. thermophila Sevcik & Hippa sp. nov. Four previously described species are recognized in the collected material: Planetella arenariae (Rubsaamen, 1899b), P. fasciata (Meigen, 1818) sp. restit., P. gallarum (Rubsaamen, 1899a), and P. granifex (Kieffer, 1898). For each of these species, DNA sequences are provided, as well as detailed illustrations of the male terminalia and male flagellomeres. Four additional species are represented only with larva, female or incomplete specimens. The phylogeny of European Planetella is tentatively reconstructed based on the combined analysis of three gene markers (28S, 16S, COI), but without providing any new infrageneric classification. The phylogenetic placement of the genus Planetella within the subfamily Cecidomyiinae is reconstructed based on four gene markers (18S, 28S, 16S, COI). The monophyly of Planetella is well supported, as well as its placement in the supertribe Cecidomyiidi. The genera Acodiplosis Kieffer, 1895 and Putoniella Kieffer, 1896 appear as the closest relatives of Planetella. The delimitation of the tribe Hormomyiini is discussed.