Species / Drepanocheilus Triliratus
Stromboidea
- Drepanocheilus triliratus Stephenson, 1941
- Drepanocheilus triliratus Kiel & Bandel, 2002 (junior homonym)
Original description of Drepanochilus triliratus by Stephenson, 1941, p. 308:
- "Shell small, turreted, with spiral angle of 32°. Whorls about 6, regularly convex on the sides. Suture compressed, deeply impressed. Protoconch broken away. Body whorl inflated above, sharply constricted on the base; periphery marked with a prominent, narrow primary spiral which rises a little as it approaches the broken outer lip; below on the base are 2 successively weaker, widely spaced spirals; the lower of the two interspaces bears 2 weak secondaries, the upper one the weaker; the rest of the base below and the anterior extension are covered with about a dozen closely spaced fairly regular, small ribs which become successively somewhat weaker from above downward. Above the peripheral ridge the body whorlis ornamented with 19 narrow axials which are broadly concave in trend toward the aperture, and are much narrower than the interspaces. About a dozen fine, fairly regular, spiral threads override the axials; the axials override the peripheral ridge, producing nodes thereon, but die out in the first interspace below. The peripheral ridge becomes weaker posteriorly and fades out on the penultimate whorl, and on the whorls of the spire the axials extend to the second basal spiral which forms the bottom of the sutural depression. The axials number 16 on the penultimate whorl and about the same number on the antepenultimate whorl; occasional, irregularly spaced axials are enlarged to form varices. The expanded outer lip is badly broken away, but the aperture is lanceolate, with an acute posterior angle, and converges to a short narrow canal in front. The columella is slender, smooth and straight."
Locus typicus: State Highway 22, 2 1/2 miles west of the courthouse at Corsicana (loc. 17368), Navarro County, Texas, USA
Stratum typicum: Nacatoch sand, Navarro Group, upper Cretaceous
Types: Holotype USNM no. 76963
Dimensions of the holotype: Height 17+ mm., diameter 7.5+ mm.
Locality: Neylandville marl, Navarro group: Corsicana road 2 1/2 miles north of Corbet, Navarro County, Texas, USA
Drepanochilus triliratus Stepenson in Sohl, 1960, pl. 11, fig. 12
- image courtesy of the U.S. Geological Survey
Original description of Drepanocheilus triliratus by Kiel & Bandel, 2002:
- " The high spired shell has eight or more volutions bearing fine curved axial ribs and irregularly occurring varices. Three beaded spiral ridges are present on the body whorl. The inner lip of the aperture is reflected, and the posterior canal attached to about three whorls of the spire. The holotype is 22 mm high and 10 mm wide.”
Locus typicus: The valley system between Torallola, Toralla and Sensuy near Pobla de Segur in the Tremp Basin, Lleida Province, Autonomous community of Catalonia, Spain.
Stratum typicum: The Campanian of the Puimanyons Olistbostrom, upper Cretaceous
Types: Holotype: GPI Type Kat. no. 3903 and Paratype: GPI Type. Kat. no. 3902; (Paläontologisches Institut und Museum, Universität Hamburg, Germany)
Etymology: Named for its three spiral ridges on the body whorl
Drepanocheilus triliratus Kiel & Bandel, 2002; Holotype; Campanian, upper Cretaceous; Torallola, Conca de Dalt Municipality, Lleida Province, Autonomous community of Catalonia, Spain; Coll. GPIH no. 3903
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