Patella aspera Lamarck, New to Norway

Abstract

DURING an investigation of the ecology of the genus Patella in Norway last summer I had the opportunity of studying large populations of the genus from Western Norway. A close scrutiny of the morphology and habitat, as well as their behaviour in aquaria showed that two species were involved, the common species P. vulgata L. and P. aspera Lamarck. This is the first record of P. aspera for Norway, thus extending its northern limit from north-eastern Scotland¹ to western Norway. The fact that P. aspera was observed to spawn in the area investigated shows that the species is an established one in western Norway. P. aspera has this year been found from Stavanger (the island Rott) in the south to the islands west of Bergen in the north. Further investigations of distribution northwards will be undertaken this autumn.