Ontogenetic modifications produce similar phenotypes in distantly related click beetles (Coleoptera: Elateridae)

Abstract

Abstract We analyze the relationships of the click beetles (Elateridae) Paulusiella Löbl, 2007, and Analestesa Leach, 1824 (=Cebriognathus Chobaut, 1899). Both are incapable of jumping, with soft-bodied habitus caused by the incomplete sclerotization of the cuticle during the metamorphosis and unknown females. Their phylogenetic positions have been an uncertain issue. We use mitochondrial genomes and nuclear genes to test their current placement in Cebrionini (=Cebriognathini) and Elaterinae incertae sedis, respectively. We recover Paulusiella as a sister to Hemiops Laporte, 1838 (Hemiopinae) and Analestesa as one of the serially splitting branches in Cardiophorinae, both with robust support. Paulusiellini trib. nov. is proposed for Paulusiella in Hemiopinae due to high morphological disparity. Analestesa is transferred to Cardiophorinae, and Cebriognathini Paulus, 1981, an earlier synonym of Elaterinae: Cebrionini, is a synonym of Cardiophorinae Candèze, 1859. The click beetles affected by ontogenetic modifications converge to similar forms. As a result, their phylogenetic position cannot be reliably inferred by morphological analyses and needs to be validated by molecular data. Paulusiella and Analestesa represent two additional cases of the shift to incomplete sclerotization in elaterids raising the total number to 6. The present transfers of extant taxa between subfamilies call for a cautious interpretation of morphology in other soft-bodied groups, including the taxa described from amber deposits.