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Species / Pietteia Cretacea


Original Diagnosis of Pietteia cretacea by Kase, 1980, p. 309:

  • "A large-sized species of Pietteia characterized by long outer lip spine and a long spine at ramp angle of body whorl three-fourths volution back from outer lip. Aperture broad. Spire whorls with broad subsutural ramp and ornamented by eight to ten slightly prosocline raised axial ribs. "

Original Description of Pietteia cretacea by Kase & Maeda, 1980, p. 309:

  • "SheIl larse-sized having high, evenly tapering and slightly coelconoid spire. Incremental angle in neighbourhood of earliest teleoconch about 20. Spire attaining about one half of total shell height with eleven angularly inflated whorls. Suture impressed. Protoconch poorly known, consisting of about two smaIl and smooth whorls. Each spire whorl with concave and steeply inclined broad rampe Spire whorls sculptured by axial ribs and spiral cords. Axial ribs strong, weakly prosocline, round-topped, much narrower than their interspaces and ten in number on penultimate whorl but eight or less on early whorls. Axial ribs obscure on ramp, but abruptly appearing near ramp angle. Spiral cords very fine and regularly spaced, two of which prominent at middle position of whorl and becoming more or less tuberculated at intersections with axial ribs. Posterior carination continuing with outer lip spine and appearing near boundary between penultimate whorl and body whorl and gradually strengthened towards aperture. Several prominent spiral cords present below anterior carination. Outer lip spine thick, stout, and extending nearly horizontal at first but rat her abruptly turned slightly backwards with pointed end. Aperture broad, elongate subovate, rounded posteriorly, and angulated anteriorly in harmony with siphonal canal. Outer lip rounded; posterior part of out er lip thick and opisthocyrt, and anterior part thin and sharp at its edge. Inner lip regularly concave with a well-delimited heavy callus. On body whorl a long and thick spine situated at the ramp angle three-fourths volution back from outer lip.

Locus typicus: Kimigahama, Choshi, Chiba, Japan

Stratum typicum: Kimigahama Formation, Barremian, Cretaceous

Pietteia cretacea Kase, 1980, Holotype; Coll. NSM PM15050, photo Takuma Haga

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