Phylogenomics reveals climate-driven range expansion of the antlion tribe Megistopini (Neuroptera: Myrmeleontidae: Nemoleontinae) during the Oligocene-Miocene transition

Myrmeleontidae (antlions and owlflies) represents the most diverse family of Neuroptera (lacewings), while the higher-level classification and evolutionary history has yet been investigated comprehensively. Here we present a comprehensive molecular phylogenetic and biogeographic analysis of the antlion tribe Megistopini, a poorly known group without the well-known pitfall-building larval behavior but primarily inhabiting sand or rock debris, based on Ultraconserved Elements (UCE) data. The monophyly of Megistopini was strongly supported, comprising some genera previously considered as members of Nemoleontini, i.e., Indoleon Banks, 1913, Negrokus Navás, 1930, Paraglenurus van der Weele, 1909, Thaumatoleon Esben-Petersen, 1921, and Yunleon Yang, 1986. The attribution of Gymnocnemia Schneider, 1845, Nedroledon Navás, 1914 to Megistopini was also confirmed by the molecular analysis. We establish a new genus Himaleon gen. n. to accommodate some species that are classified as incertae sedis within Nemoleontinae, i.e., H. binatus (Yang, 1987) comb. n., H. cancellosus (Yang, 1987) comb. n., and H. vartianorum (Hölzel, 1972) comb. n. Our biogeographic study suggests that Megistopini likely originated in the Zagros-Iranian Plateau-Himalayas-Hengduan Mountains during the mid-Oligocene. Later, the uplift of the Qinghai-Xizang Plateau, along with the surrounding orogenic movements and climatic changes, led to a radiation of Megistopini during the Miocene, which spread in Eurasia. Moreover, our results suggest that the presence of opposable pretarsal claw, a common character in slender-legged antlions, is the ancestral state of Megistopini and was secondarily lost in some genera, also not appearing correlated to habitat choice.