Abstract
Xiphocentronidae (200 spp., 8 genera) and Psychomyiidae (~600 spp., 8 extant genera) are closely related families of aquatic insects (Trichoptera), which clades diverged during the early Cretaceous when the mean global temperature was 10ºC warmer than today. Currently these families are distributed in freshwater ecosystems around the world. The Xiphocentronidae are mostly restricted to th…