That is a Dersa clam. No doubt there, they like to be placed in the sand with medium to low currents. They tolerate the lower light levels but still require VHO and MH. The Dersa clam is the easiest of clams to keep. If your LFS sold you a Corcea at a much higher price you need to let them know. Any person with experience in SW knows that is a Dersa, that being said, they still are a nice clam, with good coloring, so enjoy, just research clams next time.