Molecular identification and description of pelagic young of the rockfishes Sebastes constellatus and Sebastes ensifer

Five rockfish juveniles (15.0-30.4 mm SL) collected in midwater trawls from offshore banks off the coast of California were identified by using a combination of morphological and molecular characters. All had pigment patterns consistent with members of the subgenus Sebastomus, but each required the use of molecular markers for species identification. Using DNA sequence data from the mitochondrial cytochrome b, we identified the juveniles as a transforming larva of Sebastes constellatus and a transforming larva and three pelagic juveniles of S. ensifer. We provide detailed descriptions of the specimens and compare our results with the developmental stages of other species of Sebastes of the subgenus Sebastomus. We found some differences in structure and pigmentation that might allow identification of these young stages by traditional means, but more descriptive work is necessary. The use of molecular tools can thus be successfully used to complement traditional identification efforts to solve problems unassailable by morphological and pigment characters alone.