Description of a new species of Simulium (Nevermannia)(Diptera : Simuliidae) from Japan

Abstract

A new black-fly species, Simulium (Nevermannia) artum sp. nov., is described based on male, female (dissected out of pupa), pupal and larval specimens collected from Tochigi and Hokkaido, Japan. This new species is assigned to the vernum species-group and appears to be most closely related to S. subcostatum (Takahasi) in that it has a combination of the following characters; katepisternum bare, female genital fork without any projection directed anteriorly on each arm, pupal frons with three long trichomes on each side, cocoon simple, and larval rectal organ with 0-2 secondary lobules on each lobe. However, S. artum is easily distinguished from S. subcostatum and other known related species by the pupal gill with four long slender filaments usually arising together at the same level from the very short common basal stalk.