Steinichnus Bromley and Asgaard, 1979


DESCRIPTION: Horizontal to subhorizontal, subcylindrical-shaped, unlined burrows with structureless burrow fill; sometimes can be partly backfilled. Oval in cross section. Burrow walls contain series of narrow transverse ridges or scratch marks, sometimes ropey in appearance.

BEHAVIOR(S): Locomotion, and most likely deposit feeding behavior. Scratches on the burrow wall are created by the organism excavating and moving sediment out of its path (Hasiotis, 2002).

ENVIRONMENTAL SETTINGS: Continental terrestrial; constructed in moist to wet habitats at or near to the sediment-water-air interface associated with alluvial and lacustrine environments. Mainly found in sediment along riverbanks, back-swamps and splays, and pond or lake shorelines but always constructed in the vadose zone. The burrows signify areas of high-water tables or standing water that is relatively fresh. Found along perennial, intermittent, and ephemeral waterbodies or temporary waterbodies associated with wet seasonal to wet climates.

POSSIBLE TRACEMAKERS: Mud-loving beetles or mole crickets. The trace is constructed by the adult burrowing and pushing its way through relatively firm, moist medium just below the sediment surface.

GEOLOGIC RANGE: Triassic-recent.

ADDITIONAL REFERENCES: Metz 1993, Hasiotis 2002, 2006, Gillette et al. 2003

REMARKS: Ekdale et al. (1984) reassigned to Spongeliomorpha carlsbergi, however, Metz (1993) suggested that the ichnogenus Steinichnus be retained for the continental. Hasiotis (2002) retained because the morphology does not fit the morphologic criteria of Spongeliomorpha.

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