Camptonectes bellistriatus (Meek, 1860)
MEEK, F. B. 1860. Descriptions of New Fossil Remains Collected in Nebraska and Utah, by the Exploring Expeditions under the Command of Capt. J. H. Simpson, of U.S. Topographical Engineers [extracted from that officer's forthcoming report.]. Proceedings of the Academy of Natural Sciences of Philadelphia, 12: 308-315. [p. 311]
1860 Pecten bellistriata Meek, 1860
Camptonectes bellistriata; R. P. Whitfield, 1880, Paleontology of the Black Hills of Dakota, plate 4, figures 6-11.
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«PECTEN BELLISTRIATA.-- Meek. Shell of medium size, subcircular, sometimes wider than long, thin, compressed, nearly or quite equivalve; hinge straight and very short; posterior wing small or nearly obsolete, obliquely truncate; anterior wing small, vertically truncate at the extremity, and in the right valve separated from the margin below, by a distinct more or less angular sinus, from which a shallow flat groove, extends obliquely to the beak; beaks of both valves small, and rather compressed; surface ornamented by numerous fine, arched, bifurcating, striae, crossed by extremely small, closely arranged concentric bines, which are often nearly obsolete on the radiating striae over the more convex portions of the valves, but quite distinct in the slender depressions between, to which they impart a punctate appearance. Length (broad variety) 2.26 inches; breadth, 2.65 inches; convexity 0.64 inch.
Locality and position. Same as last. ['Jurassic beds at Red Buttes, on the North Platte, lat. 42º 50', long. 106º 40' west.']» FIELDING BRADFORD MEEK, 1860
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Description: Shell is sub-circular in outline, thin, only slightly convex. Ornament consists of fine striae radiating from the umbo and increasing in number by intercalation as they diverge. These are crossed by fine concentric striae to give a very fine reticulate pattern in which the radiating striae are dominant.
Figured specimen: JM213. From Mobil Oil Woodley Sinclair South Illerbrun X-3-7 well in Lsd. 3, Sec. 7, Twp. 10. Rge. 18 W. 3rd. Meridian, Saskatchewan. Depth 4468.5 feet, in calcareous shale 19.5 feet above the base of the lower member of the Vanguard Formation.
Remarks: Only one specimen was found. It is smaller than the described specimens of other authors but the ornament is quite distinctive. It has also lost the hinge line and ears, making a full description impossible.
PATERSON, D. F. 1968. Jurassic megafossils of Saskatchewan with a note on Charophytes. Department of Mineral Resources, Geological Sciences Branch, Sedimentary Geology Division. Report No. 120: 135 p., pls. 1-26. [p. 40]
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Camptonectes bellistriatus Meek; D. F. Paterson, 1968, Jurassic megafossils of Saskatchewan with a note on Charophytes, plate 12, figures 3a, 3b.
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