Atlantic Oyster Drill (also known as the Oyster Drill)
Phylum: Mollusca, Class: Gastropoda, Order: Neogastropoda, Family: Muricidae, Genus: Urosalpinx, Species: Urosalpinx cinerea · Muricidae (Murex and Rock Snail family) · Gastropod (univalve), whole shell, spiral shape
Species
Urosalpinx cinerea
Shell Type
Gastropod (univalve), whole shell, spiral shape
Family
Muricidae (Murex and Rock Snail family)
Size
Approximately 0.5 inches (1.2 cm), which is typical for an adult of this species. Adults generally range between 0.5 to 1.0 inch.
Color & Pattern
Off-white to grayish-brown base with subtle darker banding or reddish-brown flammules. The colors appear slightly worn and sun-bleached from wave action.
Rarity
Very Common
Habitat
Shallow marine and estuarine environments, particularly rocky shores, oyster reefs, mudflats, and bays in intertidal and shallow subtidal zones.
Geographic Range
Native to the northwest Atlantic coast of North America from the Gulf of St. Lawrence to Florida; introduced globally to Europe and the Pacific coast.
Description
A small, sturdy fusiform shell featuring prominent rounded axial ribs and fine spiral cords. It has a relatively short spire, a well-defined oval aperture, and a short, notched siphonal canal.
Key Features
Roughly oval aperture, distinct axial ribs crossed by fine spiral threads, and a small overall size with a short siphonal canal.
Collector Value
Low commercial value due to its abundance and small size, but a common educational and beginner collection specimen.
Condition Notes
Worn and weathered condition with surface erosion, minor chipping on the outer lip, and fading of the original color pattern. Collectibility grade is Fair.
Interesting Facts
The Atlantic Oyster Drill is a notorious predator of commercial oysters and other bivalves, boring holes into their shells using its radula and acidic secretions to feed on the soft tissue inside.
Ecological Role
Acts as an important carnivorous predator controlling bivalve populations, though it can become a destructive pest in oyster aquaculture.
Similar Species
Thais haemastoma (Florida Rock Shell), which is typically larger and possesses more pronounced tubercles or spines.
Beach Finding Tips
Look in shell piles along estuarine beaches, near oyster beds, or sift through fine shell drift during low tide.