Iakttagelser av storflackiga kungsnattslandan Semblis phalaenoides vid Backtorpet i Vastmanland
- ISSN: 0013886X
The Spotted caddis fly (Semblis phalaenoides) is very rarely collected or observed in Sweden, despite a large distribution area. Observations made in 2000 at a small intermittent stream next to the home of the author suggests that the larvae may accidentally be removed from its original habitat of clear running waters and drift downstream during periods with extremely heavy rainfall. The larvae became concentrated in an unusual high number to a small river pond without aquatic vegetation. The emergence of adults in June coincided with the end of the flowering period for Lilac (Syringa). Only one male and two females were observed in flight. Four females were found resting in the vegetation and on a road crossing the floodgate of the pond. In August and September 14 large larvae were scraped in the pond with a net. They were found on the sparse terrestrial vegetation, which had been bent towards and just beneath the water surface. The collected larvae were mainly fed with freshly killed mosquitoes, flies and tiny juveniles of fish. The larvae were later released. No adults or larvae were observed in 2001-2002, despite a more intense search in a wider section of the river.