Intraspecific diversity within the three clam species. (A) Relative abundance of the 14 clam haplotypes detected in the aquariums and in situ. (B) Haplotype networks of the three species. The haplotypes are identified by a colour gradient: P. aureus in yellow, R. decussatus in green, and R. philippinarum in red. The size of each circle is proportional to the number of reads of each haplotype found both in aquariums and in situ.