Noetia ponderosa, or the ponderous ark clam, is a marine clam in the family Noetiidae.
Description The shape of the shell is rounded trigonal, almost as high as long, with 27-31 squared radial ribs divided by fine incised lines, and a distinctive brown or black periostracum. The exterior and interior of the shell is a white color. Size approximately 50–60 mm.
<div align=center> Right and left valve of the same specimen:
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Distribution Atlantic coast of North America, ranging from Virginia to Florida, West Indies, Gulf of Mexico, and Caribbean Central America.Abbott, R.T. & Morris, P.A. A Field Guide to Shells: Atlantic and Gulf Coasts and the West Indies. New York: Houghton Mifflin, 1995. 11.
Habitat Noetia ponderosa typically resides in shallow subtidal or tidal soft sandy substrates.
References