2.66. Clavate-shaped borings
Unbranched, clavate.
Remark: Clavate borings; aperture narrower than main chamber and may be circular, oval, or dumb-bell shaped; main chamber may vary from subspherical to elongate. Usually made by bivalves which may be preserved in situ (see Savazzi, 1999b).
Diagnosis. – Club-shaped macroborings (see emended diagnosis in Kelly & Bromley 1984).