Zebra Nerite / Hawaiian Nerite (Pipipi)
Phylum: Mollusca, Class: Gastropoda, Order: Cycloneritida, Family: Neritidae, Genus: Theodoxus, Species: Theodoxus neglectus · Neritidae (Nerite family) · Gastropod, whole shell with a globose, ear-shaped spiral form and a flattened columellar deck.
Species
Theodoxus neglectus
Shell Type
Gastropod, whole shell with a globose, ear-shaped spiral form and a flattened columellar deck.
Family
Neritidae (Nerite family)
Size
Approximately 0.5 inches (12-15 mm) in diameter, which is typical for adult specimens of this endemic Hawaiian species.
Color & Pattern
The exterior exhibits a weathered grayish-black base with subtle darker banding and axial streaks. The inner aperture is partially visible, showing smooth white to grey enamel. The overall coloration is somewhat sun-bleached and worn from wave action.
Rarity
Commonly found along rocky Hawaiian shorelines, though specific endemic species require targeted searching among intertidal rocks.
Habitat
Found primarily in high-energy intertidal zones, clinging tightly to basalt rocks, tide pools, and areas where freshwater streams meet the ocean.
Geographic Range
Endemic to the Hawaiian Islands, commonly encountered along rocky shorelines in Oahu and neighboring islands.
Description
A sturdy, compact marine gastropod with a low, rounded spire and a wide, semi-circular aperture. The surface features fine spiral striations and growth lines characteristic of nerites, adapted to withstand crashing waves on rocky shores.
Key Features
Globose shape, depressed spire, heavily calcified inner lip (columellar deck) with a flattened shelf, and strong tolerance for intertidal wave action.
Collector Value
Low commercial value, but highly desirable for regional shell enthusiasts and collectors focusing on endemic Hawaiian marine life.
Condition Notes
Worn condition with moderate surface erosion due to intertidal exposure and wave tumbling. The outer layer shows bleaching, grading this specimen as Fair to Good for a casual beach collection.
Interesting Facts
Locally known in Hawaii as 'pipipi', these snails are culturally significant and were traditionally gathered for food or used in shell lei making by Native Hawaiians.
Ecological Role
Acts as an important herbivore, grazing on microalgae and diatom films on intertidal rocks, serving as a food source for coastal shorebirds and fish.
Similar Species
Other nerite species such as Nerita picea (Black Nerite), which is generally darker, smoother, and larger.
Beach Finding Tips
Look along rocky basalt benches, tide pools, and the splash zone during low tide on windward shores like Laie, Oahu.
Notes
Laie oahu