Allozymes characterize sibling species of bipolar Priapulida (Priapulus,Priapulopsis)

Electrophoretic polymorphism of glucosephosphate isomerase (Gpi^*) and phosphoglucomutase (Pgm ^*) polymorphisms were assayed in the bipolardisjunct species pairsPriapulus caudatus/P. tuberculatospinosus andPriapulopsis bicaudatus/Priapulopsis australis (phylum Priapulida). Numbers of genotypes fromGpi ^* alleles and 14Pgm ^* alleles generally did not show deviations from Hardy-Weinberg expectations in composite populations sampled over geographic distances up to 500 km linearly measured. This genetic pattern suggests efficient population cohesion in a phylum where pelagic larvae have not been observed. Sibling species in generaPriapulus orPriapulopsis from northern and southern polar seas did not share identical allozyme alleles.