毛蚶、泥蚶、橄榄蚶的核型比较分析

The karyotypes of diploid Scapharca subcrenata, Tegillarca granosa and Estellarca olivacea were studied in trochophores by means of hot-dropping method and could be described by 20m+12sm+6st with NF=70, 22m+12sm+4st with NF=72 and 18m+18sm+2st with NF=74, respectively. The diploid chromosome numbers were all 2n=38.The sex chromosomes and the satellites were not found. It was considered that Tegillarca granosa was more advanced than the other two species by the method of comparision on dissymmetry. The clustering analysis was made by group mean method, the result showed that the evolutionary degree of Estellarca olivacea lay between Scapharca subcrenata and Tegillarca granosa and the specific relationship of Estellarca olivacea and Scapharca subcrenata was more closer.