Overview

This ancient family occurs in Australia ( Nannochorista , 3 or 4 spp.; N.S.W., Vic., Tas.), New Zealand ( Microchorista , 1 sp.) and South America ( Nannochorista , 3 spp.). Adults are small (fore wings 5.5-8.5 mm), the wings tinged with brown, unmarked or with greyish brown bordering most cross-veins. Venation reduced with fewer cross-veins than in other families and Rs apparently only 3-branched (R 2 possibly joining R 1 as a cross-vein). Rostrum short, slender, with mandibles not reaching the acute apex. Compound eyes relatively large, protruding. Basistyles of male broadly joined medially; dististyles cheliform. S8 and S9 of female divided by median membranous zone. Larvae elongate, slender, with 2 caudal hooks; eyes compound in Nannochorista , simple in Microchorista . Adults in low vegetation near streams and lakes. Larvae aquatic, occurring in accumulations of silt in shallow, slow streams, carnivorous, feeding on larval chironomids and probably other larval Diptera. Riek (1954) provided a key to the Australian species. Pilgrim (1972) described the larva, pupa and habitat preferences of Microchorista (as Choristella ).