Unbranched, ovoid.

Category of architectural design: 2.65. Pouch borings.

Diagnosis (revised): Elongate, straight, or arcuate chambers in bone with steep margins and concave flanks throughout, long axis parallel to substrate surface.

Macroboring; substrate osteic; tracemaker invertebrate.

Emended diagnosis: Discrete hollow ellipsoidal to drop-shaped borings considered chambers bored into the surface of inner spongy, outer cortical bone or as subcortical borings with a spongy bone base and a compact bone ceiling. The bases are flat to rounded with smooth to engraved walls perpendicular to the bone surface. The bases can be flat or tapered towards one side. Structures may be isolated but commonly form dense, locally overlapping concentrations. They appear as single-chamber
borings or as a composite trace connected with entrance tubes. The chamber is two to six times longer than its diameter.
Remarks: Emendation of the ichnogeneric diagnosis is considered
necessary to include the presence of composite traces and subcortical chambers with a defined ceiling. This diagnosis was modified from the one proposed by Benyoucef and Bouchemla (2023).