Abstract
Morphological characters and isozyme patterns of selected specimens of the genus Squalidus were investigated so as to elucidate the nature of an unusual variant in Lake Biwa. Two specimens proved to be of intermediate type on the basis of principal component analysis of 16 external characters and five vertebral counts, and allelic composition of their isozyme patterns. They were considered to be hybrids between S. chankaensis biwae and S. japonicus japonicus.
