Diversification of myrmecophilous Clavigeritae beetles (Coleoptera: Staphylinidae: Pselaphinae) and their radiation in New Caledonia

Clavigeritae (Coleoptera: Staphylinidae: Pselaphinae) comprise a supertribe of specialized myrmecophile rove beetles that display numerous behavioural, chemical and anatomical modifications associated with socially parasitic lifestyle. Due to the extreme morphological diversity clavigerites, their systematic relationships, patterns character evolution host ant use have been challenging infer. Here, we resolve deep divergences within by assembling molecular dataset encompassing breadth tribal diversity. We classify into six tribes: extinct Protoclavigerini, recent Tiracerini, Mastigerini sensu nov., Clavigerini Lunillini nov. Disarthricerini stat. The previously recognized subtribes Clavigerodina, Apoderigerina, Dimerometopina, Hoplitoxenina, Miroclavigerina, Theocerina Thysdarina are demonstrated as polyphyletic or highly derived internal clades hereby synonymized latter. Colilodion – a enigmatic taxon proposed be earliest‐branching lineage Clavigeritae – is revealed unrelated is transferred Pselaphitae. provide treatment newly‐discovered endemic genera from New Caledonia infer phylogenetic affinity Australian tribe Tiracerini. zoogeographic distribution early‐branching lineages in India region indicates possible Gondwanan origin supertribe. Extant diversified Eocene onwards, correlated rise modern ants. present evidence for island radiations both Madagascar during Oligocene‐Miocene. Using newly‐created dataset, analyse demonstrate widespread convergence morphology extends virtually all traits. Counterintuitively, however, characters postulated involved beetle‐ant communication amongst most invariant, least convergent. spectrum many species broad, contradicting co‐cladogenesis hosts instead implying switching. speculate whether variability truly adaptive, opposed product ‘morphological drift’ body parts under weak selection inside colonies, potentially very small effective population sizes.