Lindapecten acanikos (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. 46, pl. 11, figs. 1-2]
1926 Chlamys (Lyropecten) acanikos Gardner, 1926
J. Gardner, 1926, plate 11.
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«Shell rather thin and very easily broken, large and quite compressed. Umbonal angle acute and approximating 90°, the arc included between the dorsal margins slightly exceeding 180°, Radials narrow, abruptly elevated, rounded upon their summits, persistent to the outer margin, normally 17 in number, each of them, as a rule, cut by two linear sulci which divide the summit into three subequal lirae. Sides of ribs and intercostal areas also closely lirate, each thread bearing a series of small spinose processes, those upon the medial thread on the costal and upon the medial thread of the intercostal areas the most produced. Intercostal areas deep, concave, usually narrower than the costals. Inner margins sharply fluted. Auricles of moderate size, the anterior in the right valve angular, produced, cut off from the submargin by a deep byssal notch threaded with 6 or 7 scabrous lirations. Anterior submargin very narrow and free from ornamentation. Posterior auricle of right valve trigonal, cut off from the narrow unsculptured submargin by an acute angle; left auricles larger than the right, finely threaded, not sharply separated from the similarly sculptured submargins. Ctenolium including 4 or 5 rather prominent denticles. Ligament area very narrow. Resilial pit small, trigonal, the lateral margins well elevated. Cardinal margin of right valve bent over the left. Cardinal crura obscure. Adductor scar large, subcircular, slightly posterior, placed well up toward the umbones.
Dimensions: Altitude, 36.0 millimeters; latitude, 35.0 millimeters; semidiameter, 7.0 millimeters. Type: U. S. Nat. Mus. No. 352450. Type locality: No. 7893, Boynton Landing, Choctawhatchee River, Washington County, Fla. Larger but less perfect individuals attain an altitude of 63.0 millimeters. The species, however, does not seem to reach the dimensions of its nearest relative Chlamys madisonius. The costals are usually more numerous by two than in sayanus, much more persistent, and less finely sculptured, both longitudinally and concentrically. Pecten pleurinominis Woodring (= P. thetidis Dall) is quite closely allied, though the costals of the Bowden species are more numerous and the secondary liration usually coarser. The individuals collected along Chipola River are all immature and badly worn. It is the common Chlamys, however, at Boynton Landing on the Choctawhatchee and in the environs of White Springs on Suwannee River, Columbia County, and packs the fuller's earth beds at Quincy in Gadsden County. Occurrence: Chipola formation, localities 10609p, 10610c, 7893p, 2212p, 2213p, 2566p, 3704a, 3173c, 2302p, 7468r , 6175c, 6769c, 4976c, 6775c, 6776c, 360p, 6800c, 5613c, 6208r, 6209p, 5629a, 6196c, 6197c, 4986c, 2380p, 7847a.» JULIA GARDNER, 1926
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