Scientific Classification
| Kingdom: Animalia |
| Phylum: Mollusca |
| Class: Bivalvia |
| Order: Pectinida |
| Family: Pectinidae |
| Genus: Chesapecten |
| Species: Chesapecten madisonius (Say, 1824) |
Information
Geological Range
Paleogeographic Distribution
Stratigraphic Occurrences
| Chowan River Formation [Questionable/rare] |
| Duplin / Raysor Formations [Uncommon] |
| Raysor Formation |
| Tamiami Formation [Questionable/rare] |
| Yorktown Formation [Abundant] |
| Choptank Formation |
| Calvert Formation |
| Calvert Formation (Plum Point Member) |
Remarks
Common name: n/a
Synonymy: n/a
Type specimen, locality, and stratum: n/a
Other voucher specimens: n/a
Descriptions:
Original Description (from Say, 1824, p. 134-135):
“Much compressed, with about sixteen striated ribs.
Description. Shell rounded, much compressed; the whole surface covered with scaly striae: ribs elevated, rounded, with about three strife on the back of each; intervening grooves rather profound: ears equal, sinus of the ear of the superior valve profound, extending at least one third of the length of the ear.
Length rather more than four inches and a half; breadth four inches and four-fifths.
In magnitude this shell is justly entitled to compare with the preceding; but it differs in being much less convex, and in having a much more profound sinus in the ear of the superior valve. Three specimens, from which the above description was taken, belong to the Academy, and were presented by Mr. Watson.”
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Measurements: n/a
Other remarks:
Stratigraphic notes: Choptank Formation: Age not resolved beyond “Miocene”.
References: n/a
Online resources: n/a
Page history:
Some of the content on this page was originally published on the Neogene Atlas of Ancient Life on October 7, 2014. It was developed by Jonathan R. Hendricks and colleagues and migrated here in 2026.
This page was last modified on October 28, 2026 by Jonathan R. Hendricks.
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