To make a comparison between R. philippinarum and other bivalve species, the nucleotide sequences and ESTs from C. gigas, M. galloprovincialis, L. elliptica and B. azoricus were obtained from GenBank and from dedicated databases, when available. [93] . Unique sequences from these databases (based on gi number) were used from each of the databases. These sequences were compared by BLASTn against the longest contig from each of 29,679 R. philippinarum clusters with a cut off e-value of 10e-05. Hits to R. philippinarum sequences were represented in a Venn diagram.