Overview

The adults can usually be recognised by the axial condition of Rs of the hind wing, and the spinose gnathos in the male. The larva of Cosmiotes synethes pupates in a flimsy cocoon. It mines in the leaves of grasses, and has been reared from wheat. The known pupae of Australian species referred to Elachista are without a cocoon. [Traugott-Olsen and Nielsen 1977.]

Description

Very small; head smooth-scaled; ocelli present or absent; scape sometimes with pecten; proboscis rarely vestigial; maxillary palps 1- or 2-segmented; labial palps recurved, porrect or drooping; hind tibiae usually with long hair-scales; fore wing lanceolate, R 5 to costa; hind wing lanceolate, Sc+R 1 remote from Rs which extends in a nearly straight line through or near axis of wing, cell usually closed; female with frenulum of 2 bristles; abdomen rarely with dorsal spines; gnathos usually with 1 or 2 spinose knobs. Larva with crochets uniordinal, rarely biordinal, in complete or broken circle, or transverse bands; leaf- or stem-miners, usually in grasses or sedges. Pupa usually with protuberances and exposed, abdomen without movement, attached by cremaster and central girdle, sometimes in flimsy cocoon.