Phylogenomic analysis of Tachinidae (Diptera: Calyptratae: Oestroidea): a transcriptomic approach to understanding the subfamily relationships

Tachinidae is the second most species-rich family of Diptera. It comprises four subfamilies, and all of its members have parasitoid habits. We present the first phylogenomic analysis of Tachinidae using transcriptomic data, based on 30 species. We constructed four datasets: three using translated data at the amino acid level (100% coverage, with 106 single-copy protein-coding genes; 75% coverage, with 1359 genes; and 50% coverage, with 1942 genes). The trees were estimated by analysing four matrices using maximum likelihood and maximum parsimony inferences, and only minor differences were found among them. Overall, our topologies are well resolved, with high node support. Polleniidae is corroborated as a sister group to Tachinidae. Within Tachinidae, our results confirm the hypothesis (Phasiinae + Dexiinae) + (Tachininae + Exoristinae). Phasiinae, Dexiinae and Exoristinae are recovered as monophyletic, and Tachininae as polyphyletic. Once again, the tribe Myiophasiini (Tachininae) composes a fifth lineage, clade sister to all the remaining Tachinidae. The Neotropical tribe Iceliini, formerly in Tachininae, is recovered within Exoristinae, sister to Winthemiini. In general, our results are congruent with recent phylogenetic studies that include tachinids, with the important confirmation of the subfamilial relationships and the existence of a fifth lineage of Tachinidae.