Rajan:

You may kindly see this link for possible comparison and identification of your species:

http://www.europe-aliens.org/pdf/Musculista_senhousia.pdf

Best

Syed

Yes it is, look this photo. Roberto.

Dear Rajan,

yes it is Musculista senhousia (Benson in Cantor, 1842) but that name is a synonym of Arcuatula senhousia (Benson in Cantor, 1842). So Arcuatula senhousia is the valid name.

best regards

Deepak

thanks for valuable answer 

kindly suggest me about the records of this specie in India.

According to my experience in the Bohai Bay, the specimen should be Arcuatula senhousia. Anyway, if you want to make sure if it is the new records of the species in india, I suggest you should be careful and compare it with the holytype of the specimen. Hope it be useful for you.

It is very diffrent from A. senhousia living in Japan and the Sea of Japan. The Indian specimen has radial riblets on the mid-shell surface while in A. senhousia the shell is lacking sculpture except for anterior part. Look at our specimens (north-western Sea of Japan)

Rajan et al.:

Indian specimens display somewhat different features viz. spiny protuberances on posterior external surface. Comparison with type specimens of Arcuatula senhousia is warranted.

Best

Syed

The type is figured in this book: Higo S., Callomon P. and Goto Y. 2001. Catalogue and Bibliography of the Marine Shell-bearing Mollusca of Japan. Type Figures. Osaka: Elle Scientific Publications. 208 p.

This species has indeed clear radial riblets as noted by Konstantin, so it is not an Arcuatula (=Musculista) . It is in fact the Indian species Brachidontes striatulus (Hanley, 1843), see this article for specimens introduced in Singapore.

https://lkcnhm.nus.edu.sg/nus/pdf/PUBLICATION/Raffles%20Bulletin%20of%20Zoology/Past%20Volumes/RBZ%2054(2)/54rbz435-439.pdf

Specimen having the radial ribs (on third image) hence it not Arcuatula, color is similar but this type of riblets seen in the Brachidontes species. Specimen should be compared with Brachidontes striatulus.