Cruziana is a trace fossil (fossil records of lifeforms' movement, rather than of the lifeforms themselves) consisting of elongate, bilobed, approximately bilaterally symmetrical burrows, usually preserved along bedding planes, with a sculpture of repeated striations that are mostly oblique to the long dimension.

[1] Cruziana appears in non-marine formations such as the Beacon Supergroup that would have been unsuitable environments for trilobites,[1] and in Triassic sediments that were deposited after trilobites became extinct at the end of the Permian Period.

[4] Cruziana traces can reach 15 mm across and 15 cm in length, with one end usually deeper and wider than the other.

[1] The burrow may begin or end with a resting trace[5] called Rusophycus, the outline of which corresponds roughly to the outline of the trace-maker, and with sculpture that may reveal the approximate number of legs, although striations (scratchmarks) from a single leg may overlap or be repeated.

[citation needed] Several specimens of Cruziana are commonly found associated together at one sedimentary horizon, suggesting that the traces were made by populations of arthropods.