Marlinspike Auger (also known as the Spotted Auger)
Kingdom: Animalia, Phylum: Mollusca, Class: Gastropoda, Subclass: Caenogastropoda, Order: Neogastropoda, Family: Terebridae, Genus: Terebra, Species: Terebra maculata · Terebridae (Auger Snail family) · Gastropod (snail/univalve), high-spired elongated turret/cone shape; intact shell specimen
Species
Terebra maculata
Shell Type
Gastropod (snail/univalve), high-spired elongated turret/cone shape; intact shell specimen
Family
Terebridae (Auger Snail family)
Size
Measures approximately 7.5 to 8 inches in length (19–20 cm). This is an exceptionally large, mature adult specimen near the upper size limit for the species, which typically averages 4 to 6 inches (10–15 cm).
Color & Pattern
Cream to off-white ground color decorated with prominent axial bands and double rows of dark reddish-brown, chocolate, or purplish-brown square spots along each whorl. The aperture interior is smooth and glossy with light cream-to-tan tones. Patterns remain rich and distinct with minimal fading.
Rarity
Common in its natural Indo-Pacific range, but large, high-quality beach or dive specimens measuring 7–8 inches are Uncommon to Very Desirable among collectors.
Habitat
Subtidal marine environments; shallow waters ranging from 1 to 25 meters deep. Found burrowing just beneath the surface of clean sand or coral sand flats near coral reefs.
Geographic Range
Widespread Indo-Pacific region, from the Red Sea and East Africa through the Indian Ocean, north to Japan, south to northern Australia, and across the Pacific islands to Hawaii.
Description
A magnificent, heavy, multi-whorled turreted shell featuring a sharp apex and a long, tapering spire with numerous flattened whorls. Sculptured with subtle axial growth lines and divided sub-sutural bands. The small, semi-oval aperture leads to a short, recurved siphonal canal. This specimen exhibits smooth, polished enamel surfaces and classic bold chocolate-brown maculations across all whorls.
Key Features
Heavy solid shell build; long narrow high-spired turret shape with up to 20-30 whorls; distinct double rows of dark brown square spots per whorl; short siphonal canal with a twisted notch at the base; lack of strong spiral ribs on adult whorls compared to other Terebra species.
Collector Value
Moderately desirable collectible shell. Small specimens (3-5 in) are common and low value ($5-$15), but exceptional large specimens over 7.5 inches in well-preserved condition typically range from $25 to $50+ USD.
Condition Notes
Grade: Fine to Very Fine. The overall structure is remarkably complete, preserving the delicate, sharp protoconch tip and outer lip margin. Coloration is vivid with light natural wear and no heavy erosion or bryozoan encrustation.
Interesting Facts
The Marlispike Auger is the largest member of the Terebridae family. Living augers are active venomous predators equipped with modified radula teeth acting like tiny harpoons to paralyze marine worms buried in the sand. Native Pacific islanders historically used these solid, heavy shells as tools, chisels, and coconut huskers.
Ecological Role
Carnivorous benthic predator that controls populations of polychaete sand worms. It is preyed upon by crabs, stingrays, and predatory fish capable of crushing heavy shells. Status is stable and not globally threatened.
Similar Species
Terebra subulata (Spotted Auger) which is more slender with darker rounder spots and 3 spot rows per whorl; Terebra crenulata (Crenulated Auger) which has distinct small bumps/beads along the suture of each whorl.
Beach Finding Tips
Look along shallow sand flats and lagoon bottoms at low tide in tropical Indo-Pacific regions. Live animals leave long, distinct trail marks in the sand as they burrow just under the surface.
Notes
8”