Cyrnus cintranus is one of five Cyrnus species with distribution ranges restricted to western Europe. In this paper, we redescribe the poorly defined female of C. cintranus. We also draw attention to the existence of a previously unmentioned morphological feature that aids significantly in the identification of the female of C. cintranus, separating it from the females of the other Cyrnus species. New data are provided on the distribution and ecology of this species.
Keywords: Trichoptera, Polycentropodidae, caddisfly, morphology, Iberian peninsula.