A cell with a different background color represents different types of SNPs between the subspecies, and the number in each cell represents the amount of each type of SNP. Lilac: inter-subspecific SNPs, pink: northern subspecies specific SNPs, reseda: southern subspecies specific SNPs, azure: shared SNPs with the same heterozygosis type between the two subspecies and light brown: shared SNPs with a different heterozygosis type between the two subspecies. Abbreviations: N, the northern subspecies of bay scallop; S, the southern subspecies of bay scallop; A, Adenine; T, Thymine; G, Guanine; C, Cytosine; K, Thymine or Guanine; M, Adenine or Cytosine; R, Adenine or Guanine; S, Guanine or Cytosine; W, Adenine or Thymine; Y, Thymine or Cytosine.