Ensitellops species (single valve)
The shape of this little white clam (LWC) bears an uncanny
resemblance to the lasaeid
periscopiana Dall, 1899,
but the unambiguous single cardinal and divaricate external
sculpture in this R valve place it firmly in the sportellid genus
Ensitellops Olsson and Harbison, 1953. There are four (4)
Carolinian Province congeners in the Lee Collection, including the
type [En. protexta (Conrad, 1841)] and an un-named one. This
resource notwithstanding, the illustrated specimen matches
none of the shells in a dozen lots. Furthermore, elsewhere
therein is a R valve of Er. periscopiana, while resembling
this shell in silhouette, has an utterly different hinge structure,
without a true cardinal - just like the figure in Abbott (1974: 468;
sp. 5404). This is a remarkable example of conchological convergence
between LWC species in separate families.
Abbott, R. T., 1974. American seashells. Second edition. Van Nostrand Reinhold Co., New York, pp. 1-663 incl. numerous text figs. + 24 pls.
Caswell Beach, North Carolina. Digital images by David Kirsh.