Galeodea louella, (SQUIRES AND ADVOCATE, 1986)

Squires, Richard L., 2019, Revision of Eocene warm-water cassid gastropods from coastal southwestern North America: implications for paleobiogeographic distribution and faunal-turnover, PaleoBios 36, pp. 1-22 : 8-9

GALEODEA LOUELLA (SQUIRES AND ADVOCATE, 1986)

FIG. 3N–P

Galeodea sp. cf. G. sutterensis Dickerson, Crowell and Susuki, 1959 . p. 588; pl. 2, figs. 1, 4.

Phalium (Semicassis) louella Squires and Advocate, 1986 . p. 858; fig. 2.11, 2.12. Squires, 1991. pl. 2, fig. 2.

Galeodea cf. G. gallica Wrigley, 1934 . Squires and Advocate, 1986. p. 857; figs. 2.7, 2.8; Squires, 1991. pl. 2, fig. 1.

[non] Phalium (Semicassis) louella Squires and Advocate. Squires and Demetrion, 1994 . p. 130; figs. 10–11 [= Galeodea tuberculiformis Hanna, 1924 ].

Primary Type Material— Holotype LACMIP 7166 and paratype LACMIP 7167 ; both from Locality LACMIP 40665 , Maniobra Formation , Orocopia Mountains , Riverside County, southern California.

Material examined— The four specimens include: Holotype, paratype, hypotype LACMIP 8836 , and one unfigured specimen from LACMIP Locality 40662 .

Emended description— Shell small to medium size (up to 25 mm height, incomplete). Shape ovate to subglobose. Protoconch conial, paucispiral. Uppermost spire whorls rounded. Penultimate whorl partially submerged with carina bearing small, thin and narrow spinose nodes. Last whorl with three carinae; carinae evenly spaced, or second and third carinae can be closer spaced to each other. Carina on shoulder shoulder bearing 12 to 16 small, thin and narrow spinose nodes; second carina with much finer nodes; third carinae smooth. Shell covered otherwise by minute, non-cancellate spiral threads. Aperture narrrow to moderately wide. Several spiral lirae on columella at the anterior end of aperture. Anterior canal region nearly entirely missing, except for short remnant of canal showing evidence of twisting. No varices observed.

Stratigraphic occurrence— Lower Eocene. Southern California to Baja California Sur, Mexico. “ Capay Stage ”: Maniobra Formation, Orocopia Mountains, Riverside County, southern California ( Squires and Advocate 1986; Squires 1991). Bateque Formation, eastern San Ignacio area, Baja California Sur, Mexico ( Squires and Demetrion 1994).

Remarks— Preservation is moderately poor. Specimens are weathered, and the outer lip morphology can- not be determined. Galeodea louella is removed herein from Phalium (Semicassis) Mörch, 1852 and placed in Galeodea because of the overall Galeodea shape of the last whorl, several carinae with nodes, and absence of parietal columellar shield. The paratype ( Fig. 3N ) of G. louella , which is figured for the first time, shows better than its holotype how remarkably similar this species is to Galeodea gallica Wrigley, 1934 from England, France, and Denmark. Galeodea louella differs from it by having fewer small nodes on the shoulder of the last whorl.

Figures

Figure 3. See caption on the bottom of page 7.