Insight Into the Phylogeny of the Intertidal Beetle Genus <i>Aegialites</i> (Coleoptera, Salpingidae)

ABSTRACT Aegialites Mannerheim, 1853 (Coleoptera: Salpingidae) is an understudied genus. These beetles inhabit rock crevices in the supralittoral to intertidal zones. They have widely separated coxae, large claws and are flightless. Despite their limited vagility they are broadly distributed along the northern Pacific coast, from California to northern Japan. Phylogenetic relationships and species richness within Aegialites remain unclear, with historical morphological assessments yielding 4–30 species. Recent molecular studies have suggested potential cryptic species may exist. We present the first molecular phylogenetic analysis of Aegialites based on one mitochondrial gene (cytochrome oxidase I) and one nuclear gene (ribosomal internal transcribed spacer 2) from over 160 specimens across 96 localities, as well as the complete mitochondrial genome and the 18S nuclear gene for several specimens. Our phylogenetic analyses revealed three major clades, one corresponding to Alaska, Canada and Northern California; a sister clade from Russia and Japan; and a separate clade for southern California. Haplotype networks, along with calculations of FST and P‐distance, supported our findings. Based on these analyses, we have evidence for seven species of Aegialites . However, fixing the taxonomy of Aegialites will require integration of morphology and further molecular analyses.