Protocypraea, SP., SCHILDER, 1927

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 : 17-19

PROTOCYPRAEA ? SP. 2

FIGS. 6D–G

Cypraea n. sp. Smith, 1975. p. 469, 479, pl. 2, fig. 10 [as Cypraea sp. ]. Groves and Squires, 2021. p. 227.

Referred Specimens—Hypotype (of Smith, 1975) UCMP 14208 [= UCMP 6582 ] ( Figs. 6E–G ) , UCMP Locality A-9717, length 50 mm, width 30 mm, height 25 mm. Hypotype (herein), LACMIP 26456.6 , LACMIP Type 14925 ( Fig. 6D ), measures length 42.7 mm, width 27.6 mm, height 16.8 mm , LACMIP Locality 26456 [= UCMP Locality A-917, ex UCLA Locality 6456].

Occurrence— Lodo Formation (basal part), Tumey Hills, Fresno County, California, late Paleocene (Thanetian Stage) .

Remarks— Two specimens are known and their preservation is poor due to missing portions of the dorsum of both. They both outwardly resemble the hypotype of Protocypraea gualalaensis ( Anderson, 1958) ( SDSNH 33995) from the Upper Cretaceous (Campanian/Maastrichtian) Point Loma Formation, near Carlsbad, San Diego County, southern California ( SDSNH Locality 3405) as figured by Groves (1990: figs. 25, 26) and Lorenz (2017: p. 205, unnumbered figure; 2018: pl. 329, fig. 2). Generic assignment of the basal Lodo Formation specimens is provisionally based on a partially exposed spire, poorly developed dentition, and flat, smooth fossula.

Smith (1975) reported that the cypraeoideans from UCMP Locality A- 9717 in the basal Lodo Formation correlates to Mallory’s (1959) California benthic foraminiferal Ynezian Stage. Almgren et al. (1988) updated Mallory’s findings, and, with the use of calcareous nannofossils, equated the Ynezian Stage to the CP7 calcareous nannofossil biozone, of late Paleocene (Thanetian Stage) age. Saul (1983: pp. 99–102) reported the Thanetian index fossil Turritella pachecoensis Stanton, 1896 from the basal Lodo Formation.

Figures

Figure 6 (previous page) A–C. Protocypraea? sp. 1, Oyster Bay Formation, Paleocene, Appian Way, Central Is- land District, Vancouver Island, British Columbia, Canada. Dorsal (A) and (B) left (columellar) views, 1.8x, length 45.5 mm, width 29 mm, height 22 mm, of CDM 997.91.3, informal locality AP3. (C) Oblique view posterior in- complete end of shell showing sunken area encircling base of spire, width of field of vision 28.7 mm. D–G. Protocypraea? sp. 2, Lodo Formation (Paleocene, Thanetian Stage), Tumey Hills, Fresno County, central California, LACMIP Locality 26456 [ex UCLA Locality 6456]. Basal (D) view, 1.6x, length 42.2 mm, width 28.6 mm, height 18.5 mm, of hypotype LACMIP 26456.6, LACMIP Type 14925, Basal (E), dorsal (F), right (labral) (G) views, 1.44x, length 50 mm, width 28 mm, height 27 mm, of hypotype UCMP 14208, UCMP Locality A9717. H–J. Gisortia clarki Ingram, 1940, Llajas Formation (Eocene, “Capay Stage”), north side Simi Valley, Ventura County, southern Cali- fornia. Basal (H), dorsal (I), and right (labral) side (J) views, 0.5x, length 121.4 mm, width 96.4 mm, height 65.9 mm, of holotype UCMP 14844, UCMP Locality 4052. K–M. Gisortia sp., Juncal Formation (Eocene, “Capay Stage”), Whitaker Peak, Ventura County, southern California. Basal (J), dorsal (K), and right (labral) side (M) views, 0.5x, length 122 mm, width 75 mm, height 51 mm, of hypotype LACMIP 16243.1, LACMIP Type 7466, LACMIP Locality 40848 [ex CSUN Locality 848].