Application of otolith mass and shape for discriminating scabbardfishes Aphanopus spp. in the north-eastern Atlantic Ocean.

The otolith was used to investigate the variability between Aphanopus carbo and Aphanopus intermedius inhabiting the north-eastern Atlantic Ocean. The results indicate a high degree of morphological affinity between species and areas; a noticeable metabolic change in the otolith shape was noted in the specimens of A. carbo, which may be related to migrations of individuals from shallow water (closer to the continental coast) to deeper water (archipelagos of Madeira and the Canary Islands). The results suggest a single population for both species in the north-eastern Atlantic Ocean, although not conclusively.