HIGH GENETIC SIMILARITY BETWEEN GEOGRAPHICALLY DISTANT POPULATIONS INA SEA-ANEMONE WITH LOW DISPERSAL CAPABILITIES

Samples of the large sublittoral sea anemone Urticina eques (Gosse) we re collected from three localities in the northern North Sea and from one locality in the northern Irish Sea. Around the coast the total dis tance between sampling sites is approximately 1,200 km. The species ha s a large lecithotrophic larva which may not be planktonic. All sample s were screened genetically for 13 loci coding for 11 different enzyme s. Results overall indicated a high degree of genetic uniformity over the four populations sampled (F-ST = 0.025). The data are discussed in relation to current ideas of larval dispersal and results from other similar studies. It is concluded that the lack of genetic differentiat ion shown by Urticina eques is surprising given the apparently poor di spersive powers of the larva.