Marsh periwinkle

Littoraria irrorata

Family Littorinidae - periwinkles

Distinguishing
Characteristics
Gastropod (1 shell); shell spiral in shape, conical, longer than wide; color grayish white to yellow (may be greenish due to algae), light streaks of purple or reddish brown; spiraling ridges; 8-10 flat-sided whorls; sutures between whorls hard to discern; spire pointed; aperture oval with grooves inside outer lip.
Similar Species
Other area periwinkles have more distinct color patterns. The cloudy periwinkle has rounded whorls and is usually found on harder substrates.
Habitat
Bay, found attached to marsh grasses or harder substrates above the tide line
Maximum Size
3 cm (1 1/5 in)
Other Common Names
Previous Scientific Names
Comments
Air breather.