Cyclopecten diktuotus (Gardner, 1926)
GARDNER, J. 1926. The molluscan fauna of the Alum Bluff Group of Florida. Part I. Prionodesmacea and Anomalodesmacea. United States Geological Survey Professional Paper, 142-A: 1-79, pls. 1-15, 1 map [p. 49, pl. 12, figs. 13, 14]
1926 Pseudamussium diktuotum Gardner, 1926
J. Gardner, 1926, plate 12.
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«Shell small, relatively thick, porcellanous; the disk a rude sector of about 90°. Right valve moderately inflated, obliquely flattened toward the umbones;
left valve compressed. Umbones acute, projecting a little beyond the hinge line. Anterior extremity slightly more produced than the posterior. External surface covered with a crowded, microscopically fine threading crossed by sharp and regular incremental, thus forming a rather regular reticulate sculpture. Auricles small, those of the left valve not so small as those of the right; anterior auricle of left valve more sharply differentiated from the disk than the posterior auricle; anterior auricle of the right valve larger than the posterior and more sharply threaded, cut off from the disk by a shallow but distinct byssal notch; Resilial pit minute. Provinculum still retained in the form of fine ridges normal to the hinge margin, expanding slightly midway between the resilial pit and the distal extremities of the hinge. Adductor scar obscure, posterior in position. Pallial line ill defined. Inner margins smooth. Dimensions: Altitude of right valve, 3.8 millimeters; left valve of another specimen, 4.2 millimeters. Latitude of right valve, 4.0 millimeters; left valve of another specimen, 4.5 millimeters. Cotypes: U. S. Nat. Mus. No. 352454. Type locality: No. 9961, Horse Creek, 1% miles south of Oak Grove, Okaloosa County, Fla. There is a considerable degree of variation in the strength of the sculpture upon this remarkable little species. On some specimens the sculpture is almost obsolete, on others it is very sharply and evenly reticulate. However, the development of any sculpture other than the Camptonectes striation upon the disk is sufficient to distinguish this species from all the other east coast Tertiary forms. Occurrence: Oak Grove sand, locality 9961p.» JULIA GARDNER, 1926
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«Cyclopecten diktuotus (Gardner, 1926), from the Lower to Middle Miocene Oak Grove Sand of Florida, resembles C. nanus rather than C. guppyi in having fine, closely spaced radial costellae on its left valve. The right valve of C. diktuotus has radially aligned nodes on adjacent commarginal rows of prisms, as in C. oligolepis.»
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. 23]
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