Original Description of Xenophora simpsoni by Stephenson, 1893 , p. 133:
- "Shell small, trochiform, consisting of four or five volutions; spire moderately elevated with straight sides; periphery of last volution narrow, angular and somewhat produced; base nearly flat, with a rather small but distinct umbilicus. The aperture is very oblique, irregularly oval in outline, and with the inner lip slightly thickened. Surface of the spire marked by numerous faint, irregular pits and depressions that seem to have been caused by the adhesion of small pebbles and bits of shell in the manner that is characteristic of this genus. These irregularities of the surface are shown on internal casts almost as distinctly as on the shell itself. The surface also shows lines of growth that are especially prominent and strongly curved on the base of the shell."
Locus typicus: Colorado, USA
Stratum typicum: Turonian, upper Cretaceous
Measurements: "Height of one of the largest specimens, 10mm; greatest breadth, 16mm."
Xenophora simpsoni Stephenson, 1893, pl. XXIX, fig. 4, 5, 6
Etymology: "The name is given in honor of Mr. Charles T. Simpson, of the U. S. National Museum."
Comment: "There is no other described species in the American Cretaceous with which this need be compared, though comparisons with recent species show that it certainly belongs to Xenophora. There are 21 specimens in the collection, all more or less imperfect, but taken together they show all the characters of the species."
History and Synonymy
Perrilliat & Vega, 2001, p. 74:
- "Xenophora simpsoni Stanton (1893: 133, pl. 29, figs. 4-6) from the Turonian of Colorado (Figure 14), has a surface marked with depressions and holes caused by the adherence of small pebbles."
- Perrilliat & Vega 2001. A new genus and species of late Cretaceous xenophorid gastropod from southern Mexico. Veliger, 44(1), January 2 2001: 73-78, Fulltext
- Stanton, T.W. 1893. The Colorado formation and its invertebrate fauna: U.S. Geol. Survey Bull. 106, 288 p. 45 pls.