Liospira vitruvia

Phylum: Mollusca
Class: Gastropoda
Order: Murchisoniina
Family: Eotomariidae
Genus: Liospira
Species: Liospira vitruvia (Billings, 1865)

Taxonomic Details

Originally: Pleurotomaria vitruvia

  • 1865 Pleurotomaria vitruvia Billings, Pal. Foss., vol. 1, pg. 171.

Stratigraphic Occurrences

L. vitruvia_Strat

Geographic Occurrences

Map point data provided by iDigBio.

Stratigraphic Description

Sequences (Formations)

  • C5 Sequence (Whitewater, Liberty, Waynesville)
  • C4 Sequence (Arnheim)
  • C3 Sequence (Mount Auburn, Corryville)
  • C2 Sequence (Bellevue, Fairview)
  • C1 Sequence (Clays Ferry/Kope)

Identification in Hand Sample

  • Small size
  • Low spired shape
  • Sharp angulation at the midwhorl
  • Lower lip is unusually prominent and sharply curved

Liospira vitruvia from Waynesville formation of Warren County, Ohio (OUIP 1519)

Published Description

Fossils of Ohio (1996):

  • Small, very low spired, and has a sharp angulation at midwhorl.

McFarlan (1931) :

  • Diameter about 25 mm., height about ½ diameter. Characteristic features are the open umbilicus with angular margin and flattened sides, and the unusually prominent and sharply curved outline of the lower lip. Upper side of last whorl a little concave because of the slight elevation of the peripheral band. Black River-Richmond.

Ulrich & Scofield (1897) :

  • Specimens of this well-marked species are not known to exceed 30 mm. in diameter, a good average being about 25 mm. The height is about half of the width. The upper side of the last whorl is frequently a little concave because of a slight elevation of the peripheral band. The umbilicus is open but varies somewhat in size, its width being often not more than a fourth, at other times quite a third of the greatest diameter of the shell. The principal peculiarities of the species occur on the under side. Here we have first the open umbilicus with its angular margin and flattened sides; and then the unusual prominence and the sharpness of the curve of the central portion of the outline of the lower lip. The angularity of the margin of the umbilicus is of course much less marked in casts of the interior than on the shell itself. Still it is always indicated with sufficient clearness to be unmistakable to the trained observer.

Billings (1865) :

    • (Under Pleurotomaria vitruvia)Shell sub-lenticular ; spire depressed conical, smooth ; apical angle from 120° to 130° ; whorls three. On the upper side the whorls make a nearly smooth flat slope from the apex to the margin, which is narrowly rounded, and shows some indications of a band. Below the margin convex, gradually increasing in prominence to the edge of the umbilicus which is rather sharply angulated. In the umbilicus the whorls are nearly flat, and sometimes forming an indistinct staircase to the apex. The umbilicus is about one-third the whole width, abruptly ascending from the angulated edge to the apex. Surface nearly smooth.
    • The whole of the aperture has not been observed, but several silicified fragments show that the inner lip is nearly straight and approaching the vertical, slightly convex in its. upper, and concave in the lower half, giving ‘an obscure sigmoid curve. It is much extended downwards, making the depth of the body whorl at the angle of the umbilicus at the aperture more than one-third the whole height of the shell.

Width from 12 to 18 lines ; height from 9 to 12 lines.