Numerical Classification of Sharp-beaked Redfishes, Sebastes mentella and S. fasciatus, from Northeastern Grand Bank

Abstract

The distinction between Sebastes fasciatus and S. mentella has not previously been clearly established as good morphological discriminators had not been isolated. Eleven meristic and 14 morphological characters were examined individually (univariate statistics) and collectively (discriminant analysis) on 200 sharp-beaked redfish specimens representing both S. fasciatus and S. mentella which had been separated by the anatomical character of extrinsic gasbladder musculature. The result of the discriminant analysis demonstrated good (100%) separation of redfish with combinations of meristic and morphological characters. Anal fin rays, relative position of pectoral and pelvic fin to anus, number of the first left gill rakers, angle of the third preopercular spine, the fusion of the occipital–nuchal ridge, and vertebral number were good discriminators between S. mentella and S. fasciatus.Key words: Sebastes fasciatus, S. mentella, redfish, taxonomy, morphology, identification, discriminant analysis