The origin and evolution of Dolichoderinae, a dominant ant clade (Hymenoptera: Formicidae)

Abstract

Although the phylogeny of ants (Hymenoptera: Formicidae) has been extensively studied with phylogenomic techniques, the species‐rich subfamily Dolichoderinae has never been treated with genomic data. The subfamily is ecologically diverse and known for morphological homogeneity coincident with cases of extreme derivation in taxa such as Dolichoderus Lund. To study these evolutionary and ecological dynamics, a modern, comprehensive phylogenetic framework is necessary. Here, we address this gap using ultraconserved elements and 131 terminals including all genera of Dolichoderinae except Ecphorella Forel. Our results both substantiate the monophyly of tribes and most genera and recover novel relationships, facilitating a new classification of genus groups. We recover the aberrant genus Anillidris as sister to the Neotropical depauperon Paranillidris relicta ( gen. nov ., comb. nov .) within the Leptomyrmex genus group. Morphological reinvestigation reveals synapomorphies for this and other clades and illuminates patterns of homoplasy. Divergence dating and historical biogeographic analyses support an origin of Dolichoderinae in Eurasia near the Cretaceous–Tertiary boundary, with most tribes and genus groups arising in the Palaeogene. Some clades show high geographic fidelity, while others have complicated histories including multiple dispersals among bioregions. We compare model performance, highlighting areas in need of conceptual and operational attention. We synonymize the genera Arnoldius Dubovikoff ( syn. nov .) and Chronoxenus Santschi ( stat. rev .) under Bothriomyrmex Emery and treat Iridomyrmex anceps (Roger) as a senior synonym of Anonychomyrma glabrata syn. nov . We also propose the following new and revised combinations: Tapinoma indicum Forel comb. rev .; Technomyrmex epinotalis (Karavaiev) comb. nov .; Technomyrmex flavidus (André) comb. nov .; Technomyrmex incisus (Stitz) comb. nov .; Ochetellus democles (Walker) comb. nov .; † Schismiscapus caritatis (Brandão and Baroni Urbani) comb. nov . and † Schismiscapus hispaniolae (Wilson) comb. nov . Finally, we provide a synopsis of genus groups, including a suite of new diagnostic male characters, and an updated, illustrated key to workers of extant genera.