Common Bubble Snail, Paper Bubble, Atlantic Bubble
Phylum: Mollusca, Class: Gastropoda, Order: Cephalaspidea, Family: Bullidae, Genus: Bulla, Species: Bulla striata · Bullidae (Bubble shells) · Gastropod (univalve); oval/bubble-shaped with an internal spire
Species
Bulla striata
Shell Type
Gastropod (univalve); oval/bubble-shaped with an internal spire
Family
Bullidae (Bubble shells)
Size
Approximately 0.75 to 1 inch (19-25mm). Mature specimens typically range from 0.5 to 1.5 inches.
Color & Pattern
Mottled brown, tan, and grey camouflage pattern. Exterior features irregular dark splotches on a lighter cream-to-tan background. The aperture and columellar area are white to polished grey.
Rarity
Common; frequently found in drift lines on sandy beaches after high tides.
Habitat
Found in shallow marine environments, specifically intertidal and subtidal zones. Prefers sandy bottoms, mudflats, and seagrass beds where it can burrow.
Geographic Range
Common in the Mediterranean Sea and the Atlantic Ocean, including the Caribbean, Gulf of Mexico, and the coast from Florida to Brazil.
Description
An egg-shaped, thin-walled gastropod shell with a smooth, polished surface. The shell lacks an external spire; the apex is sunken or 'umbilicated.' The aperture is long and narrow at the top, widening significantly at the base to follow the shell's curvature.
Key Features
Smooth, globe-like shape; sunken apex (no visible spire); mottled brown pattern; wide aperture at the base; extremely thin, lightweight structure.
Collector Value
Minimal monetary value (typically $1-$5 USD) due to abundance, but highly desirable for beginners and coastal 'curiosity' collections because of its unique shape and smooth texture.
Condition Notes
The specimen appears to be in 'Fine' condition. It retains good color and luster, though as a beach-found specimen, it shows slight dulling. No major chips are visible on the delicate outer lip, which is rare for such a fragile shell.
Interesting Facts
The living animal is much larger than its shell and cannot fully retract inside. They are nocturnal predators/scavengers that use a specialized gizzard lined with calcareous plates to crush the shells of tiny mollusks they consume.
Ecological Role
Member of the benthos that helps control populations of smaller gastropods and foraminifera. They serve as a food source for larger crabs and predatory fish.
Similar Species
Bulla occidentalis (West Indian Bubble) is very similar and often considered a subspecies or synonym; Haminoea species (Green Bubbles) are much thinner, more translucent, and usually lack the dark mottled pattern.
Beach Finding Tips
Look in the 'wrack line' (the line of seaweed and debris left by the tide). Because they are lightweight, they are often pushed high up on the sand or trapped in clumps of seagrass.