Aim Phylogeographical ‘breaks’ often occur at biogeographical province boundaries, suggesting common causative factors. Cape Hatteras, North Carolina, on the US Atlantic coast, separates water masses of sharply differing temperature and divides the Virginian and Carolinian provinces, but has not often been detected as a phylogeographical break. We studied the black sea bass, Centropristis striata (Linnaeus, 1758), a species wi...

Understanding patterns of connectivity among populations of marine organisms is essential for the development of realistic, spatially explicit models of population dynamics. Two approaches, empirical genetic patterns and oceanographic dispersal modelling, have been used to estimate levels of evolutionary connectivity among marine populations but rarely have their potentially complementary insights been combined. Here, a spatia...

We used molecular approaches to study the status of speciation in coral reef fishes known as hamlets (Serranidae: Hypoplectrus). Several hamlet morphospecies coexist on Caribbean reefs, and mate assortatively with respect to their strikingly distinct colour patterns. We provide evidence that, genetically, the hamlets display characteristics common in species flocks on land and in freshwaters. Substitutions within two mitochond...