Stromboidea
Original description of Anchura ? elegans by Stephenson, 1941
- ”Shell small for the genus, thin, turreted; apical angle about 35 degrees: body whorl about half the total height of the shell. Whorls 5, broadly rounded on the sides, only slightly constricted below the suture. Suture closely appressed, moderately impressed. Protoconch smooth, trochoid, with 3 volutions, and with apical angle noticeably greater than that of the main spire. Axial ribs small, narrow, somewhat variable, numbering 24 to 28 on the penultimate whorl; they become smaller and less numerous toward the apex, near which they fade out; on the body whorl the ribs become coarser, wider apart, and tend to become short, strong, and nodose as they approach the aperture. Back of the outer lip the body whorl descends anteriorly in a long gentle slope, becoming constricted near the terminus; passing around toward the aperture the body whorl becomes sharply constricted. The aperture is elongated with an angular anal notch behind, and a relatively short, straight, narrow, almost pointed canal in front. The outer lip is widely expanded very much as in A.? lobata with a sharp spur above and a dull one below; the outer margin shows a tendency to thicken though none of the specimens appears to be mature; the inner lip is broadly excavated, and forms a callus which spreads somewhat forward on the base and upward past the anal notch across the penultimate whorl to and beyond the suture; this callus becomes thickened on the larger specimens. The whole outer surface, including the broad outer lip, is densely crowded with fine microscopic threads, which are somewhat variable in strength on different individuals and on different parts of the same shell; this spiral sculpture is, however, more strongly developed than in Anchura? lobata media.”
Locus typicus: Vicinity of Corsicana, Navarro County, Texas, USA
Stratum typicum: Nakatoch sand, Navarro Group, Maastrichtian, upper Cretaceous
Holotype: U.S.N.M. no. 76913; protoconch partly broken away, and the anterior canal is incomplete; height 21+ mm.; diameter, including expanded lip, 15 mm., excluding this lip 9 mm.
Anchura ? elegans in Stephenson, 1941; left and middle holotype, right paratype; Coll. USNM no. 76914
- Image courtesy The University of Texas at Austin
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