Button Snail or Littorine Shell (Alternate: Periwinkle)
Phylum: Mollusca, Class: Gastropoda, Order: Littorinimorpha, Family: Littorinidae, Genus: Nodilittorina, Species: Nodilittorina picta · Littorinidae (Periwinkle family) · Gastropod, whole shell, spiral shape
Species
Nodilittorina picta (or closely related Pacific Littorina species)
Shell Type
Gastropod, whole shell, spiral shape
Family
Littorinidae (Periwinkle family)
Size
Approximately 10-15 mm in length, which is average for this adult species. Typically range between 8 and 18 mm.
Color & Pattern
Pale pinkish-white base color with subtle mottled brownish or reddish markings forming a checkered or speckled pattern across the body whorl. The apex is pointed and slightly darker. Colors appear largely natural with minor weathering.
Rarity
Common, frequently found along suitable rocky Hawaiian shorelines.
Habitat
Intertidal zone, typically found clinging tightly to rocks, basalt, and tide pools in the splash zone exposed to heavy wave action and marine air.
Geographic Range
Endemic to the Hawaiian Islands, commonly found along rocky shores of Oahu and neighboring islands.
Description
A small, solid, conical shell with a smooth to finely textured surface. It features a pointed spire consisting of several convex whorls and a rounded body whorl. The aperture is ovate and compact with a simple outer lip, adapted for enduring pounding surf.
Key Features
Small conical shape, solid construction, low number of whorls, distinctive speckled or mottled pinkish-brown pattern, and habitat-specific adaptations for wave-swept rocks.
Collector Value
Low to moderate commercial value, highly popular as souvenir shells for local crafters and regional shell collectors focusing on Hawaiian micro-molluscs.
Condition Notes
Good condition, mostly intact with minor wear on the apex, typical of beach-drift or rock-collected specimens. Collector grade: Good.
Interesting Facts
These tiny snails are remarkably hardy, capable of surviving out of water for extended periods by sealing themselves tightly against rocks to prevent desiccation during low tides.
Ecological Role
Primary consumers that graze on microalgae, biofilms, and diatoms from rocky substrates, playing a crucial role in maintaining the balance of intertidal microbial communities.
Similar Species
Other Pacific Littorina species such as Littoraria pintado, which can be distinguished by sharper color dots and specific whorl proportions.
Beach Finding Tips
Look in high-tide zones, crevices of basalt rocks, and tide pools along rocky Hawaiian coastlines, particularly after stormy weather.
Notes
Oahu