Millipede assassins and allies ( <scp>H</scp> eteroptera: <scp>R</scp> eduviidae: <scp>E</scp> ctrichodiinae, <scp>T</scp> ribelocephalinae): total evidence phylogeny, revised classification and evolution of sexual dimorphism

Abstract

Abstract Evolution of sexual dimorphism in animals has long been of interest to scientists, but relatively few studies have reconstructed evolutionary patterns of extreme sexual dimorphism at a phylogenetic scale, especially in insects. Millipede assassin bugs ( H eteroptera: R eduviidae: E ctrichodiinae; 736 spp.) and their sister taxon, T ribelocephalinae (150 spp.), exhibit sexual dimorphism that ranges from limited to extreme, a phenomenon apparently modulated by female morphology. Here, we reconstruct the first phylogeny for the subfamilies E ctrichodiinae and T ribelocephalinae with comprehensive generic representation (152 taxa in 72 genera) using morphological and molecular data (six gene regions). The combined phylogenetic results indicate that T ribelocephalinae are paraphyletic with respect to E ctrichodiinae, and that E ctrichodiinae themselves are polyphyletic. Based on these results, we synonymize T ribelocephalinae with E ctrichodiinae syn.n. , describe three new tribes ( E ctrichodiini trib.n. , T ribelocodiini trib.n. , and A belocephalini trib.n. ) and two new subtribes ( O pistoplatyina subtrib.n. and T ribelocephalina subtrib.n. ), and revise T ribelocephalini sensu n. Ancestral state reconstruction of sexual dimorphism reconstructed limited sexual dimorphism in the ancestor of E ctrichodiinae sensu n. with at least seven evolutionary transitions to extreme sexual dimorphism within the clade. This published work has been registered in ZooBank , http://zoobank.org/urn:lsid:zoobank.org:pub:C810E20F‐D66A‐461F‐A0E6‐AB1073EA3E3C .