Discovery of a new Isonychia species with distinctive characters from southwestern China, and preliminary exploration of its phylogenetic status (Ephemeroptera, Isonychiidae).

The genus Isonychia Eaton, 1871 is widely distributed across the Holarctic and Oriental regions. However, no representatives of this genus have been reported from southwestern China, a region known for its high biodiversity. Here, we described and illustrated Isonychialatias sp. nov., a new species recently collected from Guizhou Province, southwestern China, across all developmental stages. The imagos of this new species exhibit some uncommon characters within Isonychia, such as brown mid- and hindlegs, and pale stripes on the thorax. To explore the phylogenetic status of this new species within Isonychia, a multigene phylogenetic analysis was conducted.