The Fine-ribbed Auger, Terebra protexta (Conrad, 1846), is the second most common species among the four species of the auger family Terebridae found on Sanibel and Captiva. Its shell is very similar to that of the more common Eastern Auger, Terebra dislocata, but differs from this latter by its smaller size (about 25 mm, or one inch), slightly flatter whorls, usually more numerous ribs, and less marked incised sub-sutural constriction. Its color is grayish to grayish-brown, or rarely grayish-purple.
The Fine-ribbed Auger, Terebra protexta, from Sanibel.