Polygyra cereolus (Muhlfeld, 1816)
Southern flatcone snail
There is considerable variation in the shell size of Polygyra cereolus. The height ranges from 3.5-4.6 mm and the diameter ranges from 11.5-18.2 mm. The number of whorls for this species also varies from 7-9. The discoidal shell is white with radial streaks or spots of gray or light brown on the base, giving the shell a uniform wood-brown or fawn-colored appearance. The upper surface of the shell may be completely flat or it may be slightly raised (conical) with obliquely regular rib striations. The lower side of the shell is nearly flat or slightly concave with a vortex-like umbilicus (navel). The last whorl is swollen at the end (near the aperture). The keel is weak or completely absent. The outer and basal margins of the peristome (margin/edge of the mouth) is reflected and thickened on the inside, giving it a heart-shaped appearance. The parietal margin is slightly raised, free and possesses a short, oblique tooth.
- U.S.: Alabama, Florida, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, South Carolina, Texas, Wisconsin
South America: Mexico
Pacific Islands: Hawaii
Atlantic Islands: Bermuda
This species is reported to feed on red and white clover (Trifolium spp.) and alfalfa (Medicago sativa).
- Helix cereolus J. C. Megerle von Muhlfeld, 1818, Gesellschaft naturforschender Freunde zu Berlin, Magazin etc., 8: 11, pl. 2, fig. 18a, b; Binney, 1959, Terr. Moll., 4: 90, pl. 77, fig. 23 (copy from Muhfeld); Bland, 1860, Ann. Lyc. Nat. Hist. N.Y., 7: 137, fig. 2.
- Hellix cereolus var. laminifera, W. G. Binney, 1858, Proc Acad. Nat. Sci. Phila. P. 200, nude name; cf. Bland, 1860 and Binney, 1869.
- Helix microdonta Desh., W. G. Binney, 1859, Terr. Moll., 4: 91, in part.
- Helix carpenteriana Bland, 1860, Ann. Lyc. Nat. His. N.Y., 7: 138.
- Polygyra carpenteriana Bland, W. G. Binney, 1878, Terr. Moll., 5: 284, fig. 182, pl. vi, fig. m (teeth).
- Polygyra cereolus Muhlfeld, W. G. Binney, 1878, Terr. Moll., 5: 283, fig. 181; Rhoads, 1899, Nautilus, 13: 44.
Abbott 1989; Cowie 1997; Kalmbacher et al. 1979; Pilsbry 1940; Perez and Cordeiro 2008; Pilsbry 1940