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Species / Pyktes Aspris

Stromboidea


Original description of Pyktes aspris by Popenoe, 1983

  • "Shell of medium size, usually 35 mm or less in height, with general characters of genus; shell material thin; helicocone consisting of six spire whorls and last whorl; protoconch of three smooth, regularly convex whorls about twice as broad as high; fourth to sixth whorls with obtuse bend in profile at about mid-height, and a sculpture of fine, close-set spiral lines on earlier whorl, becoming coarser and fewer with shell growth, and most strongly developed on posterior suture and periphery of whorl; axial sculpture of low, opisthocline, obscure, rather widely spaced riblets on earlier whorl, developing into distinct thickened welts extending from suture to periphery of last whorl, where these welts tend to become nodose; base of shell broadly convex posteriorly (parietally), nearly straight in profile viewed aperturally, without ornamentation except for irregularly and widely spaced, low, obscure spiral bands; posterior suture of earlier whorls situated above (posterior to) shell periphery, but advancing anteriorly with succeeding whorls, lying anterior to the periphery on penultimate and ultimate whorls; earlier sutures linear, later ones channeled; spiral angle, about 55º; growth-line nearly normal to suture posterior to shoulder, thence swinging forward (aperture-ward) in a broadly convex curve nearly to anterior tip of shell."

Locus typicus: ¼ mile north of the Oak Run Road opposite the Hathaway House, Oak Run Valley, Millville Quadrangle, Shasta County, California, USA.

Stratum typicum: Coniacian, Cretaceous

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