Phosphoglucomutase genotypes and spawning time in two species of anchovy, Thryssa hamiltoni and T. mystex, from the northwest Arabian Gulf

The polymorphic enzyme phosphoglucomutase showed a significant genetic change and seasonal excess of homozygotes in two species of anchovy repetitively sampled during the spawning periods over 2 years in the Arabian Gulf. Samples from the peak spawning periods were not in genetic equilibrium, which is unexpected as spawning stocks are thought to show the greatest level of genetic isolation, and indicate that assortative mating may occur. [Copyright &y& Elsevier]