Phylogenetic relationships of M icrodontinae ( D iptera: S yrphidae) based on molecular and morphological characters

The intrasubfamilial classification of M icrodontinae R ondani ( D iptera: S yrphidae) has been a challenge: until recently more than 300 out of more than 400 valid species names were classified in Microdon M eigen. We present phylogenetic analyses of molecular and morphological characters (both separate and combined) of M icrodontinae. The morphological dataset contains 174 characters, scored for 189 taxa (9 outgroup), representing all 43 presently recognized genera and several subgenera and species groups. The molecular dataset, representing 90 ingroup species of 28 genera, comprises sequences of five partitions in total from the mitochondrial gene COI and the nuclear ribosomal genes 18S and 28S . We test the sister‐group relationship of Spheginobaccha with the other M icrodontinae, attempt to elucidate phylogenetic relationships within the M icrodontinae and discuss uncertainties in the classification of M icrodontinae. Trees based on molecular characters alone are poorly resolved, but combined data are better resolved. Support for many deeper nodes is low, and placement of such nodes differs between parsimony and B ayesian analyses. However, Spheginobaccha is recovered as highly supported sister group in both. Both analyses agree on the early branching of Mixogaster , Schizoceratomyia , Afromicrodon and Paramicrodon . The taxonomical rank in relation to the other S yrphidae is discussed briefly. An additional analysis based on morphological characters only, including all 189 taxa, used implied weighting. A range of weighting strengths ( k ‐values) is applied, chosen such that values of character fit of the resulting trees are divided into regular intervals. Results of this analysis are used for discussing the phylogenetic relationships of genera unrepresented in the molecular dataset.