紀伊水道海域のメイタガレイ２型（ホンメイタとバケメイタ）のｍｔＤＮＡ切断型における遺伝的分化

Abstract

Genetic differentiation between two forms of flatfish, differentially called Honmeita and Bakemeita found in the Kiisuido Channel waters off the Pacific Coast of Central Japan, was investigated by restriction fragment analysis of mitochondrial DNA (mtDNA). 36 specimens of Honmeita and 32 specimens of Bakemeita were analyzed. We demonstrated 17 restriction fragment types using five 6-base recognized restriction endonucleases (BamHI, BglII, HindIII, PstI, XhoI). Five haplotypes in Honmeita and 3 types in Bakemeita were recognized, and there were no common types between the two forms. Nucleotide divergences among haplotypes of flatfishes were estimated to be 0.0074-0.0159, 0.0055-0.0115, 0.0684-0.0948, in the Honmeita form, in the Bakemeita form and between the two forms respectively. Interformal mtDNA nucleotide divergence was estimated to be 0.081. This value suggests that these two forms differentiate so highly from each other at the interspecific level. Intraformal mtDNA nucleotide divergence was estimated to be 0.0016 and 0.0012 in the Honmeita and Bakemeita forms respectively.