Description:
The hard clam has a large, heavy shell that ranges from being a pale brownish color to shades of gray and white.  The exterior of the shell, except nearest the umbo is covered with a series of growth rings.  The interior of the shell is colored a deep purple around the posterior edge and hinge. 

Habitat:
Hard clams prefer sand or muddy substrata from intertidal flats to 50 ft. in depth.  They are most abundant in shell-containing soft bottoms.

Similar Species:
M. mercenaria can be confused with a closely related species, the Southern hard clam, M. campechiensis.  However, M. campechiensis is slightly larger, and its shell lacks purple coloration on the interior surface.  It also lacks any smooth areas near its umbo. 

Range:
The natural range of the hard clam extends from the Gulf of St. Lawrence south through Texas.  Hard clams are common throughout the Indian River Lagoon. They are also farmed commercially from Indian River County northward.