Biotope and biology of Armadillidium album Dollfuss, a terrestrial isopod of sandy beaches, in the SW Netherlands

Abstract

The supralittoral isopod Armadillidium album Dollfus is common, although patchily distributed, under driftwood on the foreshore of broad sandy beaches on the outer coast of the Delta area in the SW Netherlands. The isopods are very tolerant of immersion in seawater, but are nevertheless confined to a narrow zone just above normal spring tides. A. album is a sexually reproducing isopod, with a single well-defined reproductive period in summer and a lifespan of two years. In spite of its very specialized biotope, the life cycle and reproductive strategy of A. album do not deviate substantially from those of related ubiquitous terrestrial isopods.