Siphonichnus Le Blanc Smith, and Cable, 1980

DESCRIPTION: Vertical to oblique burrows with either concave or convex backfill meniscate laminae. Circular to oval and rarely ovoid or cordiform in plan view. A vertical tube or pair of tubes may be present; if so, tube penetrates through concave, and more rarely, convex laminae.

BEHAVIOR(S): Domichnia (dwelling), equilibrichnia (equilibrium).

ENVIRONMENTAL SETTINGS: Shallow marine environments, mostly in estuarine and bay deposits.

POSSIBLE TRACEMAKERS: Bivalves.

GEOLOGIC RANGE: Carboniferous–recent

ADDITIONAL REFERENCES: Zonneveld and Gingras 2013, Knaust 2015.

REMARKS: The diagnosis of Siphonichnus by Stanistreet et al., 1980 was emended by Zonnveld and Gingras 2013 to clarify the description of the morphology of the burrow. Siphonichnus is commonly incompletely preserved due to the dynamic depositional settings prone to erosion and deposition. Incomplete specimens may be difficult to differentiate from such laminate vertical forms as Conichnus, Lingulichnus, and Teichichnus.