The richness and paucity of the spider fauna of the Belgian coast

A comparison is made between the spider species composition of twelve sandy natural areas in Flanders along a gradient from the coast dunes and salt marshes in the west to the large heathland areas in the east. All these natural areas have large numbers of rare and threatened species. The relative paucity in spider species in coastal reserves is caused by the lack of species bound to ombrotrophic Sphagnum bog vegetation and to wet oligotrophic grasslands.