Geographic variation in Prionotus punctatus (Bloch) (Teleostei, Scorpaeniformes, Triglidae): a geometric morphometric analysis

Abstract

Patterns of geographic variation in body shape were analyzed in nine population samples of the searobin Prionotus punctatus (Bloch) from the northeastern, southeastern, and south Brazilian coast, using geometric morphometrics techniques. The nine population samples were ordinated by canonical variate analysis into three groups corresponding to regions north and south of the 23C isotherm. The shape differences represent a contrast between an increase in body depth in the specimens of the northeastern coast and an elongation of the body in the remaining samples. These results suggest that there is extensive geographic variation in P. punctatus along the Brazilian coast. The patterns of geographic variation in body shape are apparently related to decreasing water temperature southward along the coast.