Phylogenetic analysis and revision of subfamily classification of Belostomatidae genera (Insecta: Heteroptera: Nepomorpha).

Recent investigations into relationships among the cosmopolitan Belostomatidae have led to recognition of the Belostomatinae, Horvathiniinae and Lethocerinae clades. Here we investigate the relationships among the genera of this family (with Appasus, Benacus and Kirkaldyia now resurrected, and three fossils: Cratonepa, Iberonepa and Lethocerus vetus) by including modifications or clarifications of both somatic and genitalic characters (including some spermatheca traits), as well as multiple genes (COI, 18S rDNA and 16S rDNA). A comparative study of these genera yielded putative homology hypotheses coded as 104 morphological characters and 1829 aligned characters. A majority-rule tree utilizing the Bayesian method [the 'master' tree with highlighted clades estimated by maximum parsimony and maximum likelihood (ML)] is as follows: (Cratonepa, Iberonepa, (Benacus, Kirkaldyia, Lethocerus), (((Horvathinia, Hydrocyrius), Limnogeton), (((Abedus, Weberiella), Belostoma), (Appasus, Diplonychus))))). Lethocerinae and Belostomatinae (now with Horvathinia included) form two monophyletic groups. Weberiella appears as the sister group of Abedus, and Belostomatini had to be reformulated. In all trees, the monophyly of Diplonychini trib. nov. (Appasus+Diplonychus) was recovered with high support indices. This study highlights a global tree based on combining the molecular and morphological data representing topologies from separate analyses, irrespective of the existence of missing data and the type of dataset. [ABSTRACT FROM AUTHOR]