Pecten (Camptonectes) martinsensis Stephenson, 1952
STEPHENSON, L. W. 1952. Larger invertebrate fossils of the Woodbine formation (Cenomanian) of Texas. United States Geological Survey Professional Paper, 242: 1-211, pls. 8-58 [p. 80, pl. 19, figs. 1-4]
«Pecten (Camptonectes) martinsensis Stephenson, n. sp.
Plate 19, figures 1-4 This species has the general form and type of ornamentation of Pecten (Camptonectes) moodyi, but differs differs in several of its characters. It averages smaller, has a much weaker development of the radial sculpture, being practically smooth over the central more inflated part of the shell, and the right anterior ear is proportionately shorter and higher; even where the flat, weak radials are present the surface has a smooth polished appearance, as preserved at the type locality. The radial ribbing is present on all the ears, but is noticeably weaker on the right anterior ear. The ribs are smaller and more closely crowded on the ears than on the main shell. The inner margins of the anterior and posterior ears diverge from the beak at an angle of about 85°. A narrow, sharp, radiating sulcus is present at the inner margin of the anterior right ear where it joins the main shell; the other three ears are rather sharply delimited at their inner margins.
Dimensions of the young cotype shown in plate 19, figures 3, 4: Length 11.1 mm, height 13.5 mm, thickness 3.3 mm. In measuring the larger shell shown in plate 19, figures 1, 2, an allowance of 4 mm is made for the width of the calcite vein that cuts it: Length 23.5 mm, height 24 mm, thickness 5.5 mm. The largest shell in the collection is about 30 mm long. Types.— Two figured cotypes, U.S.N.M. 105241a-b; 9 unfigured cotypes, U.S.N.M. 105242; all from the Templeton member on Martins Spring Branch, 0.2 mile south of a road, 2.9 miles west by north of Pottsboro, Grayson County.
Occurrence.— Grayson County: Locs. 128, 137, 152 (cotypes), 162, 164, 171; Fannin County: loc. 191. Range.— Lewisville member to Templeton member.» LLOYD WILLIAM STEPHENSON, 1952
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L. W. Stephenson, 1952, plate 19.
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