|
Ensitellops pilsbryi (Dall, 1899) (single valve) |
|
The shape of this little white clam (LWC) bears an uncanny
resemblance to the lasaeid
Erycina
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. protextus (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. Dall, W. H., 1899. Synopsis of the Recent and Tertiary Leptonacea of North America and the West Indies. Proceedings of the United States National Museum 21: 873-897, pls. 87-88. June 26. <https://www.biodiversitylibrary.org/page/15716992> |
|
|
|
Caswell Beach, North Carolina. Digital images by David Kirsh. |
|
|
