This species belongs to phylum mollusca, class-pelecypoda/Bivalvia/Lamellibranchiata , order-Eulamellibranchiata, family-Myidae. The animal looks to be Mya that is commonly known as mud clam. This animal is bivalve shell, unsegmented, bilaterally symmetrical, provided with visceral mass, foot and mantle. It is morphologically looks like Mya, however there is need to explore anatomical study of this species to confirm exact bivalve species. Also see the varieties of Mytilus, Mya and Unio species by identifying anatomical characters bcz in photographs I can not make it clear the exact species. Please also see Lutraria oblonga, Lutraria lutraria and Mytilus shell for further investigation.
Protein and DNA analysis are the two basic components of methods used to identify species; protein characterization is done via immunological, electrophoretical, and chromatographic methods (Mafra et al., 2008).