Holopea obliqua
Classification
Phylum: Mollusca
Class: Gastropoda
Order: Euomphalina
Family: Holopeidae
Genus: Holopea
Species: Holopea obliqua Hall, 1847
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1847 Holopea obliqua Hall, Pal. New York, 1, p. 170, pl. 37, figs. 2a-d.
1855 Turbo obliquus Emmons, Amer. Geology, 1, pt. 2, p. 158, pl. 5, fig. 8.
1860 Turbo obliquus Emmons, Man. Geol., p. 98, fig. 87.
1889 Holopea obliqua Lesley, Geol. Surv. Pennsylvania, Rep. P 4, p. 283.
1896 Holopea cf. obliqua Sardeson, Bull. Minnesota Acad. Nat. Scil, 4, p. 74, pl. 3, fig. 5.
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Sequences (Formations)
Sequences (Formations)
- C5 Sequence (Lower Whitewater)
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Identification in Hand Sample
- Moderately low spired
- Strongly rounded whorls ornamented with growth lines
- Spire very short
- Three to four volutions
- Aperture somewhat circular, outer lip thin
Holopea obliqua from the Arnheim Formation of Hamilton, Ohio (OUIP 1066)
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Davis (1998):
Davis (1998):
- Note rounded shoulder and lack of ornament. Sub-Edenian.
Fossils of Ohio (1996) :
- Holopea oblique Hall is medium sized and moderately low spired and has strongly rounded whorls ornamented only with growth lines. Middle Ordovician to Devonian.
Hall (1847):
- Spiral, oblique, height and breadth nearly equal; spire very short, acute at the apex, composed of three or four volutions, diminishing rapidly above, the last one very ventricose; aperture somewhat circular, entire, transversely extended, with the outer lip thin; surface smooth, or covered with fine striae. This shell has heretofore been referred to the genus Natica, from its general resemblance, though it is not probable that it is a true Natica. It is more oblique, and the spire is shorter and more abruptly acute than in either of the other species described. The aperture, in two specimens examined, is rounded upon the outer side, contracting towards its junction with the body whorl. In the largest specimen seen, the surface is marked with vertical curving undulations or rounded ridges; but these appear due to age, or other circumstances not constant in their influence, though something of the kind is obscurely visible in another specimen. The volutions are somewhat more appressed at their junction than the succeeding species./li>
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