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Southwest Florida Shells with Emphasis on Sanibel & Captiva

By José H. Leal

Family Littorinidae

Littoraria nebulosa

(Lamarck, 1822)

Cloudy Periwinkle

Shell with five or six rounded whorls. Sutures slightly indented. Sculpture of incised spiral lines on entire shell. Well-defined parietal shield tinged with mauve. Color grayish-white, gray, or bluish-gray with irregular brown markings. Earlier whorls usually dark-brown, aperture yellow within. This species prefers to settle on dead tree trunks or dead wood structures. The two photos of the unusually bluish-shelled snails living on dead black mangrove trunks were taken by Dr. José H. Leal on Cayo Costa State Park on October 25, 2014.