Stromboidea
Original Description of Anchura (Perissoptera) hannai by Allison, 1955
- " Shell moderately small, high-spired; volutions about nine; whorl diameter over twice height, profile strongly convex with point of maximum convexity approximately at whorl center; later whorls ornamented by about fourteen heavy and smoothly rounded axial ribs; axial ribs concave posteriorly; superimposed spiral ornamentation of approximately fifteen narrow ribs; subdued axial ribs of body whorl represented by spiral keel at point corresponding to highest development of axial ribs on preceding whorls; body whorl keel extended outward and slightly posterior from outer lip as long slender digitation at angle of about 55º to axis; two additional but very short digitations extend perpendicularly and slightly anteriorly respectively from outer lip, fused together; anterior canal long, possibly curved; about twenty spiral ribs on anterior portion of body whorl, similar to those of spire; posterior portion of outer lip thickened, extending to penultimate whorl."
Locus typicus: Punta China, Baja California State, Baja California Peninsula, Mexico
Stratum typicum: middle Cretaceous
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