北海道オホーツク海沿岸におけるイカナゴ属魚類3 種の耳石形状の変異

抄録

Inter- and intraspecific variations in 2-dimensional otolith morphology were investigated in three sympatric species of Ammodytes (Perciformes: Ammodytidae) from Japan, viz., A. japonicus Duncker and Mohr, 1939, A. hexapterus Pallas, 1814 and A. heian Orr, Wildes and Kai, 2015. Size-dependent measurements and elliptic Fourier analyses of otolith outlines failed to show significant differences among the three species. However, both investigating methods revealed intraspecific variations relative to body length in each species, indicating ontogenetic changes in otolith morphology. The occurrence of several outlier specimens suggested a variable pattern of ontogenetic changes among individuals and/or between developmental stages.