Phylogenetic utility of five genes for dipteran phylogeny: a test case in the Chironomidae leads to generic synonymies

Abstract

In this study we examine the utility of three mitochondrial (COI, COII, 16S) and two nuclear (CAD and EF-1a) markers for estimating lower-level phylogenetic relationships within the dipteran family Chironomidae. As a test case we use species of the genus Micropsectra and the putatively closely related genera Krenopsectra, Parapsectra and Paratanytarsus. We also examine the phylogenetic evidence for the currently accepted species groups within the genus Micropsectra. In our results, highly variable EF-1a sequences within some species indicate the first find of paralogous gene copies in nematocerous Diptera. Among the other genes, COI is found to have the weakest while CAD contains the strongest phylogenetic signal. The resulting phylogeny displays a well-supported, but paraphyletic Micropsectra with regard to Krenopsectra acuta and five Parapsectra species, indicating taxonomic synonymy of these genera with 100% posterior probability. The genus Parapsectra is polyphyletic within Micropsectra while Paratanytarsus remains monophyletic although with low posterior probability. Micropsectra acuta, M. bumasta, M. fallax, M. nohedensis, M. mendli, M. uliginosa, M. chionophila, M. nana, M. styriaca and M. wagneri will all be new combinations as a consequence of the synonymy.