Identification of two eel species, Anguilla japonica and A. anguilla by discriminant function analysis

Discriminant functions as a simple method for identifying two eel species, Anguilla japonica and A. anguilla, were developed using four morphometrical characteristics. In order to test the validity of the functions, species discrimination using the functions was carried out on a total of 162 eels obtained from four natural waters (a river in Kannonji City and Lakes Shinji, Jinzai and Ikeda), and the result was compared with that of identification by PCR-RFLP analysis. This analysis showed that discrimination using the functions was more than 90% correct, indicating that this was an effective identification tool. The species discrimination showed that the rates of occurrence of A. anguilla in each area were 10% for the river in Kannonji City, 15.1% for Lake Shinji, 20% for Lake Jinzai and 93.5% for Lake Ikeda.