Original description of Anchura ? plenocosta by Stephenson, 1941:
- "In size, form, and general appearance this species is much like Anchura? lobata Wade. The axial ribs are thicker and extend fully developed to the suture above on all the whorls except the ultimate. The body whorl is slightly constricted just below the suture, but a constriction is lacking on the other whorls. Approaching the expanded outer lip the axials become definitely shortened, the last 2 or 3 of them forming nearly round, rather prominent nodes. The surface of the body whorl is densely crowded with fine microscopic spiral lines of irregular trend; these are much too fine to be shown in the illustration. The outer lip is incomplete around the margins in the holotype, but, as more completely preserved in one of the paratypes, it appears to be essentially like that of A.? lobata."
Locus typicus: near Kaufman, Kaufman County, Texas, USA
Stratum typicum: Nakatoch sand, Navarro Group, Maastrichtian, upper Cretaceous
Type specimens: Holotype U.S.N.M. no. 76912; height 38+ mm., diameter exclusive of the expanded outer lip 16 mm., diameter including this lip 28+ mm; 8 unfigured paratypes, U.S.N.M. no. 20988.
Anchura ? plenocosta in Stephenson, 1941; holotype
- Image courtesy The University of Texas at Austin
History and Synonymy
Arrhoges (Latiala) cf. A. plenocosta in Sohl, 1960, pl. 11, fig. 17
- image courtesy of the U.S. Geological Survey