A Comparative Study on Morphological Characters of Stock of The Anguillid Elver From Representative Estuaries in China Coast

This paper deals with comparison on morphological characters of the elver (Anguilla japonica Temminck et Schlegel) stock.Samples were collected from seven representative estuaries,Wan Quan He (Hainan),Dong Gang (Taiwan),Han Jiang (Guangdong),Min Jiang (Fujian),Qian Tang Jing (Zhejiang),Chang Jiang (Jiangsu) and Yalu Jiang (Liaoning) Rivers,during the upstream migration periods from 1992 to 1994.According to the 75% rule of Mayrs subspecies identifications,no subspecies had been found among stocks from various estuaries by means of coefficient of difference (CD).The discriminate function analysis of seven meristical and morphometrical characters indicated that there were significant difference (F＞F0.01) among stocks from most estuaries in the same years.We believed that these differences might be caused by genetically heterogeneity.Since the change of these differences in various years was unregular,it may be closely related to the random of drift and range of elvers.