Occurrence of the Genus Orthogonis HERMANN (Diptera, Asilidae) in Japan, with the Description of a New Species

摘要

A new species, Orthogonis nitididorsalis, is described based on the specimens from Kyoto and Ehime Prefectures, Japan, and is the first representative of the genus Orthogonis HERMANN from Japan. The genus Orthogonis HERMANN, 1914 is characterized as follows (HERMANN, 1914; JOSEPH and PARUI, 1981): the end vein of the discal cell and the end of 3rd medial cell both are aligned in a straight line or parallel, and proboscis is short and massive. Most of the Orthogonis species is confined to the Orientaland Australian regions (OLDROYD, 1975). The occurrence of the genus in Japan was first recorded by TAGAWA and YAMAMOTO (2000) as Orthogonis sp. from Odamiyama, Ehime Prefecture. Subsequent examination of this species revealed that this was an new species which had a close relation to the Indonesian species, O. obliquistriga (WALKER, 1861). In the following lines, I will describe this new species with illustrations of habitus and structural features to distinguish it from other species of Orthogonis.