Systematic revision and molecular phylogenetics refine the generic classification of the bark louse family Stenopsocidae (Insecta: Psocodea: Psocomorpha)

Abstract

Psocomorpha, as one of the suborders of the order Psocodea, represents a large group of free-living bark lice. The phylogenetic relationships among/within the major groups, such as families, subfamilies, tribes, etc., of the bark lice need extensive investigation. The family Stenopsocidae belongs to the infraorder Caeciliusetae, which is a large group of Psocomorpha and is one of the common groups in Asia. Here we infer the intergeneric relationships of Stenopsocidae based on the mitochondrial genes and the nuclear 18S rRNA. The result supports the monophyly of Stenopsocidae and suggests the paraphyly of the genus Stenopsocus. Combining the morphological evidence, we propose a new genus, namely Neostenopsocus gen. n., which includes a number of species previously placed in Stenopsocus. The checklist of this new genus is provided. This new genus can be distinguished from Stenopsocus by the glabrous forewing CuP. In the revised classification system, Stenopsocidae includes four genera: Graphopsocus, Malostenopsocus, Neostenopsocus gen. n., and Stenopsocus. A key to the genera of Stenopsocidae is provided. We also present the diagnostic characters for each of these genera.