Limited Genetic Divergence in Populations of the Sheepshead in the Northern Gulf of Mexico
Two named subspecies of sheepshead exist in the northeastern Gulf of Mexico (Archosargus probatocephalus probatocephalus and A. p. oviceps). These subspecies are morphologically distinctive; previously published data was used to demonstrate that frequency distributions of each of five meristic counts are significantly different between the subspecies (P < 0.05). However, genetic characteristics suggest limited divergence. For instance, Bayesian structure analysis of microsatellite genotypes indicated that all sampled populations of Gulf of Mexico sheepshead constitute a single stock,...