Helicotaphrichnus commensalis Kern, Grimmer et Lister, 1974

Diagnosis: Helicotaphrichnus is a partly excavated, partly deposited fossil tube that is found ony in the columellar wall of gastropod shells. The tube may be single, or it may double back on itself once or twicw to form tight U or S shapes, but it always follows the helical path of the chamber of the gastripod shell.