Background: The Psychodinae of the Afrotropical Region remain poorly understood. Slightly under 200 species have been described, but many countries have received very little attention from collectors and even countries where significant collection efforts have taken place have rarely had their collections studied in detail by specialist taxonomists.
New information: Perithreticusneglectus sp. n. is described from the West Usambara Mountains, Tanzania, based on a male specimen collected in 1990. The new species is similar to Perithreticusanderseni Kvifte, 2015, which occurs in the same forest reserve, but can be separated by several genitalic characters, including the hypandrium well-developed with sclerotised anterior and posterior margins, gonocoxites narrower, the gonostyles with the slender apex shorter, the parameres shorter without pronounced basolateral projections and the surstylus with slightly fewer tenacula. The world fauna of Perithreticus now comprises five described species, of which two occur in the Afrotropical Region.
Keywords: Diptera; Psychodidae; Tanzania; West Usambara Mountains; moth flies.
Gunnar Mikalsen Kvifte.