Multigene phylogeny of blister beetles (Coleoptera, Meloidae) reveals extensive polyphyly of the tribe Lyttini and allows redefining its boundaries

Meloidae is a beetle family with about 3000 species divided into three subfamilies and 16 tribes. Included is the tribe Lyttini containing 33 genera and about 400 species. However, the boundaries of Lyttini have proved hard to define since the systematics of this tribe have repeatedly changed. In this study, we investigated the phylogeny of Lyttini and tested for its monophyly based on a comprehensive molecular dataset of mitochondrial (COI and 16S) and nuclear (CAD and 28S) genes including 57 genera and 385 species representing most of the tribes of Meloidae. Further phylogenetic analyses were performed on a reduced taxon set (51 genera and 135 species covering 60% of the generic diversity of Lyttini) in order to maximize the number of loci and minimize missing data. Phylogenetic results strongly supported the monophyly of most of the tribes of the subfamily Meloinae, apart from Lyttini, which is split into 11 phylogenetically distinct lineages scattered throughout the tree. Based on these results, we restrict the tribe Lyttini to the genera Alosimus Mulsant, Lydus Dejan, Lytta Fabricius, Muzimes Mulsant & Rey and Oenas Latreille, all exclusive to the Holarctic region. The relationships among the remaining genera previously included in Lyttini and the other 10 lineages representing ‘non-Lyttini’ tribes remain to be clarified. This study also provides a number of nomenclatural acts [including Pseudolytta n. stat.; Lytta (Taurilytta) n. subgen.; Lytta (Teratolytta) n.stat.; Mimovesperus resurrected; Denierella = Epicauta n.syn.; Psalydolytta = Epicauta n. syn.] and working hypotheses for future investigations on the systematics of Meloidae.