Nodipecten collierensis collierensis (Mansfield, 1932)
MANSFIELD, W. C. 1932. Pliocene fossils from limestone in Southern Florida. United States Geological Survey Professional Paper, 170-D: 43-56, pls. 14-18. [p. 47, pl. 16, figs. 3, 5]
1932 Pecten (Nodipecten) pittieri collierensis Mansfield, 1932
1932 Chlamys (Lyropecten) pontoni Mansfield, 1932
1932 Chlamys (Lyropecten) pontoni Mansfield, 1932
W. C. Mansfield, 1932, plate 16.
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«Shell large, orbicular, moderately ventricose, equivalve, and nearly equilateral, the posterior region being slightly more produced. Sculptured with broad, nearly flat, weakly undulating ribs (seven on the left valve and eight on the right) separated by little wider interspaces. The ribs are broader over the middle of the disk and narrower on each side. Top of ribs sculptured with five to eight coarse, raised threads separated by narrower interspaces. Spaces between major ribs marked with three to five coarse, weakly undulating threads and occasionally with a finer thread. Submargins sculptured with six to eight radial threads, which are equal in strength to the intercostal threads. Ears ornamented with rather coarse radiating riblets.
Dimensions: Holotype (catalogue No. 371326, U. S. Nat. Mus.), left valve, length, 142 millimeters; height, 125 millimeters. Paratype, right valve (catalogue No. 371327, U. S. Nat. Mus.), length, 100 millimeters; height, 104 millimeters. Type locality: Station 1/1176, Tamiami Trail, about 11 miles east by north of Marco, Collier County, Fla. The subspecies differs from Pecten (Nodipecten) pittieri Dall [Dall, W. H., New species of fossil shells from Panama and Costa Rica: Smithsonian Misc. Coll., vol. 59, No.2, p. 10, 1912], a species collected from Moin Hill, near Port Limon, Costa Rica, horizon a, in having a more ventricose shell which is ornamented with wider and fewer (by two) ribs. The surface of the ribs on the subspecies, although slightly corroded, does not distinctly indicate the vaulted scales, which are strongly developed on the left valve of P. pittieri. Dall, in his original description of P. pittieri, placed it in the section Lyropecten, but it appears to be more closely related to the section Nodipecten than to Lyropecten. Pecten pittieri Dall and the new subspecies appear to be more closely related to Pecten (Nodipecten) nodosus Linnaeus, of the east coast, than to Pecten (Nodipecten) subnodosus Sowerby, of the west coast. The new subspecies appears to be an intermediate form between Pecten pittieri and Pecten nodosus Pecten (Nodipecten) veatchii Gabb, a Pliocene species from Cerros Island, off Lower California, appears from the illustration to be closely related to my new subspecies. Occurrence: Pliocene. Station 1/1176 (type locality, 2 valves), station 1/1180 (paratype locality, 1 valve), and station 1/1178 (2 valves).» WENDELL CLAY MANSFIELD, 1932
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«On the basis of so little well-preserved material, nothing can be said about the variation of Nodipecten nodosus in the Dominican Republic Neogene. However, specimens from the early Pliocene of Venezuela identified as N. collierensis (Mansfield, 1932) by Smith (1991b: pl. 9, figs 3-4, pl. 10, fig. 6) appear rather to be N. nodosus. They show rib patterns, node development, and secondary costation comparable to the Dominican Republic specimens but differ in being less flaring and having narrower umbonal angles.
Comparison.—In the material from the Neogene of the Dominican Republic available for this study, Nodipecten nodosus is the only species having a central-sector rib pattern of N n Nc n N and is thus readily distinguished from N. colinensis colinensis and N. c. vokesae, in which the rib pattern is N 2r Nc 2 r N. Nodipecten collierensis s. l. and N. pittieri also have a central-sector pattern of N n Nc n N, but differ from N. nodosus in other characters. Nodipecten collierensis is a middle to late Pliocene species that ranged through the southeastern United States to the Gulf of Mexico coast of Mexico (see following discussion of evolution). It differs from N. nodosus in having more distinctly paired, flatter ribs on its left valve and lacking nodes on its right valve (Smith, 1991b: pl.10). Nodipecten pittieri, on the basis of its holotype from the late Pliocene Moín Formation of Costa Rica, is much more broadly flaring than N. nodosus with nodes in the form of open flanges giving way in later ontogeny to coarsely costate ribs and interspaces without nodes or flanges. Although Smith (1991b: 91) indicated that either N. collierensis or N. pittieri could be present in the Gurabo Formation of the Dominican Republic, I have found no defi nite trace of them in the collections on hand. Nodipecten arnoldi, a species in the late Pliocene to early Pleistocene of the Caribbean coastal regions of northern South America and nearby islands, has a central-sector pattern of N n Nc n N, but differs from the species mentioned above in having a much thicker, more massive shell with very coarse costae in rib interspaces.
Nodipecten nodosus, which lives today in the coastal waters of the Antilles and along the Caribbean and Atlantic coasts of Central America and northern South America, has commonly been confused with N. fragosus (Conrad, 1849), which now lives along the coasts of the southeastern United States from Cape Hatteras to southern Florida and in the Gulf of Mexico from Florida to Mexico, with an outlying population in Bermuda. Both species have the N n Nc n N rib pattern in the central sector of their left valves but differ in rib spacing, rib profiles, and the degree of development of minor ribs adjacent to disk flanks. The ribs of the right valve of N. fragosus have flatter crests and are more distinctly paired, with wider spaces between pairs, than in N. nodosus. On left valves, N. nodosus commonly has two minor ribs between the central sector and the adjacent disk flank, with the lateralmost ribs commonly nodose. In contrast, N. fragosus commonly has only a single rib between the central sector and the disk flank; if a second rib is present, it commonly is difficult to distinguish from the disk flank and is not nodose. The degree of node development is highly variable in both species, but nodes can be completely absent in some specimens of N. fragosus. Evolution.— Smith (1991b: 94) claimed that "Nodipecten nodosus evolved directly from N. collierensis in the late Miocene or early Pliocene." The basis for this claim are specimens identified as N. collierensis from the late Miocene and early Pliocene of Venezuela (Smith, 1991b: pl. 8, fig. 6, pl. 9, figs 3-4, pl. 10, fig. 6). These specimens differ from typical N. collierensis from the Tamiami Formation of Collier County, Florida, in having slightly more rounded, less distinctly paired ribs on the right valve and stronger somewhat broader minor ribs in the central sector of the left valve. In this sense, these specimens are closer to N. nodosus than is typical N. collierensis, and the Venezuelan specimens might indeed represent the beginning of the N. nodosus lineage as well as the beginning of a separate group that includes more typical N. collierensis of the southeastern United States, which evolved in the Gulf of Mexico and Florida, giving rise to extant N. fragosus.»
WALLER, T. R. 2011. Neogene Paleontology of the Northern Dominican Republic. 24. Propeamussiidae and Pectinidae (Mollusca: Bivalvia: Pectinoidea) of the Cibao Valley. Bulletins of American Paleontology, 381: 1-197, pls. 1-18. [p. 125, 126]
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Nodipecten collierensis (Mansfield); J. T. Smith, 1991, Cenozoic Giant Pectinids from California and the Tertiary Caribbean Province, plate 9, figures 3, 4.
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«Description: Shell medium to large, subcircular, slightly compressed; ribs low, nodes typically low, occasionally absent; upper valve with seven low, narrow ribs alternating in strength; lower valve with eight subequal ribs. Secondary sculpture of fine radial threads.
Occurrence: Pliocene. Carolinas – lower Goose Creek Limestone; Florida – Tamiami Limestone, lower Pinecrest. Type locality: About 11 miles northeast of Marco, Collier County, Florida. Discussion: Nodipecten collierensis differs from N. peedeensis in its smaller size, lower inflation, and less vigorous sculpture. Shelving at resting stages is weak or absent. The large population from the Berkeley Quarry is remarkably uniform in morphology, varying principally in degree of node development.»
CAMPBELL, M. R. & L. D. CAMPBELL. 1995. Preliminary Biostratigraphy and Molluscan Fauna of the Goose Creek Limestone of Eastern South Carolina.Tulane Studies in Geology and Paleontology, 27 (1-4): 53-100, pls. 1-5. [p. 81]
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Nodipecten collierensis (Mansfield); M. R. Campbell & L. D. Campbell, 1995, Preliminary Biostratigraphy and Molluscan Fauna of the Goose Creek Limestone of Eastern South Carolina, plate 1, figures 1, 3.
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