Larval Description, Adult Feeding Behavior, and Phylogenetic Placement of Megalopinus (Coleoptera: Staphylinidae)

Abstract

Abstract Larvae of the genus Megalopinus, of the monobasic subfamily Megalopsidiinae, are described for the first time. Larvae can be distinguished from all other known staphylinid larvae by the presence of a mandible with a subapical bladelike process, and are differentiated in detail from other larvae of the staphylinine group of subfamilies in a key. To confirm the identity of Megalopinus larvae, which have not been reared to adults, we compared partitions of 28 adult and 20 larval morphological characters derived from members of the stenine group (Megalopsidiinae, Euaesthetinae, Steninae) and three staphylinid outgroups (Oxyporinae, Pseudopsinae and Piestinae). Partitioned cladograms were similar with the only difference being the placement of Pseudopsinae as sister taxon to the stenine group (adult characters) or included within it (larval characters). Characters were combined and one tree was produced with the following relationships: Megalopsidiinae (Pseudopsinae (Steninae, Euaesthetinae)). Megalop...