Description of the immature stages and the adult female of Aulacigaster africana, the first known for the Afrotropical Aulacigastridae (Diptera: Schizophora)

Abstract

Hitherto unknown adult female and the immature stages (egg, 2nd and 3rd instar larvae) of Aulacigaster africana Barraclough, 1993, from South Africa are described and illustrated. Submarginal lateral setae of female 8th sternite are strong, ordered in one row, and far less numerous than in A. leucopeza. Eggs are asymmetrically and broadly oval in lateral view, the dorsal part with a pair of dark flanges, and medial hatching strip, with dark cellules in more or less two rows. The lateral and ventral parts of the egg have thin, partly confluent longitudinal ribs. The anterior spiracle of 3rd instar larva has 15 or 16 pairs of twig-like processes (6-8 pairs in A. leucopeza). The mandible is long and curved, bearing two pairs of accessory teeth. The parastomal bar is long, thin and dorsally curved at its middle; the intermediate sclerite consists of three parts (the posteroventral one clearly divided into an anterior ventral and a posterior longish section); there is an additional long sclerite, of an intricate form, between the intermediate sclerite and mandible. The 2nd instar differs from the 3rd instar larva in that the mandible has no accessory teeth. The dorsal cornu is very short; only the long ventral process of the intermediate sclerite seems to be characteristic.