<i>Brachygyna incae, </i>a new genus and species of psychid from Peru with atypical larval biology (Lepidoptera: Psychidae).

Abstract

Brachygyna incae, a new genus and species of Psychidae, is described from Machu Picchu, Peru, where the larva feeds on lichens growing on the walls of the ancient Inca fortress. The female is brachypterous, with wings approximately half the size of the males. Proposed synapomorphies for the genus include the unusual degree of wing reduction in the female, the loss of the basal pair of tibial spurs in the hindlegs, the narrowly V-shaped form of the saccus and the short, stout, ventral lobe of the valva in the male genitalia. Prepupal larval behavior is atypical of the family, with the last instar larva not inverting its body prior to pupation. The larva instead maintains an upright vertical position inside the larval case prior to pupation, with the adult later emerging from a subapical slit near the point of attachment of the case and not from the caudal end of the case in the manner typical of other Psychidae.