Cypraedia, Swainson, 1840

Groves, Lindsey & Squires, Richard L., 2023, Revision of northeast Pacific Paleogene cypraeoidean gastropods, including recognition of three new species: implications for paleobiogeographic distribution and faunal turnover, PaleoBios 40 (10), pp. 1-52 : 34

CYPRAEDIA SP.

FIGS. 10A–C

Cypraedia sp. Squires and Demetrion, 1990. p. 102, figs. 2.8–2.10. Squires and Demetrion, 1992. p. 31, fig. 80.

Referred Specimens—Hypotype (of Squires and Demetrion, 1990 and Squires and Demetrion, 1992) IGM 5057 ( Figs. 10A–C ), length 19.5 mm, width 13.2, height 11.9 mm. LACMIP Locality 41220b [ex CSUN Locality 1220b].

Occurrence— Middle lower Eocene (“Capay Stage”), Bateque Formation, Baja California Sur, México.

Description— Shell ovate-inflated. Spire involute. Aperture narrow, cancellate ornamentation very fine and consisting of numerous equidistant spiral ribs (about 23) crossed by longitudinal ribs. Spiral ribs tend to alternate in strength on central part of base of shell and tend to become stronger than longitudinal ribs on anterior part of base of shell. Outer lip prominent, especially its posterior end. ( Squires and Demetrion 1990, in part).

Remarks— This is a very rare gastropod. The preservation of the single known specimen is somewhat imperfect due to weathering, but the diagnostic characteristics of the genus are clearly present. In regard to its very fine cancellate structure, which is relatively uncommon on members of this genus, this specimen is most similar to the late Eocene (Bartonian Stage) specimen of Cypraedia cancellata Swainson, 1840 [= C. elegans G.B. Sowerby I, 1823 ] illustrated by Cossmann (1903: pl. 9, fig. 8) and by Cossmann and Pissarro (1910 –1913: pl. 33, fig. 162-13 [two views]) of middle Eocene age (Lutetian Stage) in France. The Bateque Formation specimen differs by having a less inflated columellar side of its shell, a narrower inner lip, the presence of spiral ribs of alternate strength on the central part of basal side of the shell, and a more projected posterior end of its outer lip.

Figures

Figure 10. A–C. Cypraedia sp. Bateque Formation (Eocene, “Capay Stage”), Mesa La Salina, Baja California Sur, México. Basal (A), dorsal (B), and right (labral) side (C) views, 2.3x, length 19.5 mm, width 13.2 mm, height 11.9 mm, of hypotype IGM 5057, LACMIP Locality 41220b [ex CSUN Locality 1220b]. D–F. Cypraeogemmula warnerae Effinger, 1938. “Gries Ranch beds,” Crescent Formation (upper part) (Eocene, “Capay Stage” to Galvinian Stage), Black Hills area, Washington. Basal (D) and dorsal (E) views, both 16x, and left (columellar) (F) view, 33x, of hypotype LACMIP 16655.37, LACMIP Type 11372, LACMIP Locality 16655 [= LACMIP Locality 41563; ex CSUN Locality 1563]. (continued on next page)