Life cycle and larval and pupal habitat of Rhyacophila nigrocephala in the midstream of the Kino-kawa River

I investigated the life cycle and habitat of the larvae and pupae of Rhyacophila nigrocephala in middle reaches of the Kino-kawa River, Nara, Japan. Monthly occurrence of larvae, pupae, and adult suggested that this species was bivoltine: the wintering generation started in November 2014 and terminated in May and June 2015, whereas the non-wintering generation started in June and terminated in October 2015. The larvae of this species were predominately found in hyporheic habitat of the riverbed. However, a few of the first instar larvae, which hatched from eggs just before sampling, were collected from the surface of cobbles in June. The later stage of the fifth instar larvae and most pupae also were collected from the surface of cobbles. These results indicate that this burrowing caddis larvae used the surface of the riverbed temporally after hatching from eggs and before pupation.