Stralopecten ernestmithi (Tucker-Rowland, 1931)
TUCKER-ROWLAND, H. I. 1931. Some new Tertiary Pectens. Proceedings of the Indiana Academy of Sciences, 40: 243-245, pl. 1 [Under H. I. Tucker]. [p. 244, pl. 1, figs. 3, 4]
1931 Pecten ernestmithi Tucker-Rowland, 1931
H. I. Tucker-Rowland, 1931, plate 1.
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«Shell ovate, rather large, heavy, with five ribs, three of which are better developed. The ribs are broad and rounded on their summits and show a marked tendency to become nodose from the umbonal region to the periphery. Interspaces wider than the ribs and deeply channeled. Both ribs and interspaces strongly, radially threaded. A fragment of a right valve shows a strongly developed, concentric sculpture of scaly lamellae over both ribs and interspaces. Beak narrow and quite pointed. Sub-margins narrow, the outer margins nearly smooth, the inner radially threaded like the rest of the disk. Ears large, unequal and radially threaded. Anterior byssal ear quite pointed and somewhat corrugated along the cardinal margin. Posterior ear somewhat less strongly threaded. Byssal sinus deep, narrow and inconspicuous. Fasciole broad. Interior fluted to the unbones. Margins crenulated. Ctenolium consists of six, prominent denticles. Resilial pit narrow, trigonal, lateral margins elevated. Cardinal margin of the right valve bent over the left. Provinculum strongly developed. Valve retains traces of a blotchy color pattern. Height 85, length 82.5, length of hinge line 60 and convexity about 20 mm.
This species differs from P. caloosaensis Dall in the shape of the ears, in the width of the interspaces and in sculpture. P. ernestsmithi shows a well developed sculpture of radial threads while in caloosaensis the interspaces are sculptured only with feeble concentric lines. The anterior byssal ear of ernestsmithi is much more pointed at the cardinal margin than that of caloosaensis. Holotype: Deposited Museum Paleontology, Cornell University. Range: Pliocene. Locality: Keith's marl pit, Neill's Eddy Landing, Cape Fear River, five miles from Acme, N. C.» HELEN IONE TUCKER-ROWLAND, 1931
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«The specimens figured from the collections in the United States National Museum are rather better than the holotype.
Shell large, moderately convex. Primary radial sculpture of 4 or 5 strong, undulating ribs and of 2 slightly less. prominent ones near the submargins; secondary, of strong, rounded cords numbering 6 to 8 on each primary, equal in strength on the radial and interradial areas, separated from one another mostly by linear interspaces; the medial riblet of the intercostals occasionally made more conspicuous than the others by wider channels, which set it apart from the adjacent secondaries. The concentric sculpture —the characteristic feature of the shell— consists of very close-set imbrications that override the secondaries of both the costal and the intercostal areas; in many individuals a suggestion of concentric undulations on the primaries, but these are never so strongly developed as in the type of Nodipecten. Submargins rather wide, not very sharply differentiated; inner submargins sculptured with concentrically imbricated lirations, usually 5 to 8; outer submargins smooth, the posterior wider than the anterior, the latter often obsolete in the right valve. Auricles large, widest at the cardinal margin; distal angles acute; right ear sculptured with 5 or 6 strong radial threads, separated by linear interspaces and overrun by concentric imbrications similar to those on the disk; left auricle sculptured with 8 to 12 feeble striations, unequal in width and separated by unequal interspaces, concentrically wrinkled but not imbricated imbricated; left ear in some individuals joined to the disk by a sharp angulation, in others by a concave area. Byssal notch probably deep; fasciole conspicuous. Ctenolium well-developed. Resilial pit narrow, deep, somewhat oblique. Hinge area in young furnished with feeble cardinal crura, which become obsolete in adults and are replaced by a wide ligamental area. Muscle scar slightly posterior and dorsal. Inner surface of valves strongly undulated by primaries. Ventral margin crenulated by secondaries. Dimensions of figured specimens (U. S. Nat. Mus. No. 325492): Right valve: Height 70.0 millimeters, width 67.0 millimeters. Left valve of another individual: Height 101.5 millimeters, width 100.0 millimeters. Both the figured specimens were collected from the Waccamaw formation at Walkers Bluff, Bladen County, N. C. This fine species is separated from C. caloosaënsis Dall, of the Florida Pliocene, by the sculptured intercoastal areas; and from C. peedeensis (Tuomey and Holmes) (pl. 6, fig. 5), of the South Carolina Miocene, and from C. nodosa Linnaeus, of the Recent fauna of the east coast, by the absence of well-defined nodes, by the fewer, coarser primaries, and by the stronger, more crowded concentric imbrications. Distribution: North Carolina: Pliocene, Waccamaw formation, Walkers Bluff, Bladen County; Neills Eddy Landing, Columbus County. This species, though by no means abundant, is fairly well represented at these two localities.»
GARDNER, J. 1943. Mollusca from the Miocene and lower Pliocene of Virginia and North Carolina. Part 1. Pelecypoda. United States Geological Survey Professional Paper, 199-A: 1-178, pls. 1-23. [p. 35]
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Chlamys (Lyropecten) ernestsmithi (Tucker) Tucker; J. Gardner, 1943, Mollusca from the Miocene and lower Pliocene of Virginia and North Carolina, plate 6, figures 6, 8.
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