Ichnofossils
Species

Cruziana dispar (Linnarsson, 1869)

Taxon description

Stachacz, 2012a

Emended diagnosis. – High, oval, symmetric hypichnion with a narrow, more or less distinct median furrow, which separates two lobes. The lobes are covered by distinct V-shaped ridges, which meet in the median furrow at an angle of 60–180°. The width of the ridges in the front and rear of the lobes can be different. The V-shaped patterns formed by the ridges are usually directed in oppo site directions at the front and rear of the traces.

Description. – Oval or slightly elongate, bilobate convex hypichnion, 70–120 mm long, 40–60 mm wide, 20–40 mm high, without distinct margins. On the surface of the lobes, distinct, regular ridges (interpreted as moulds of scratch marks), 1–3 mm wide, 3–4 mm apart, which meet in the median furrow at an angle of 60–100° and form a V-shaped pattern, oriented in one direction or in opposite directions in the front and rear parts of the oval. Generally, the ridges are thick, showing different widths in the front and rear parts of the lobes. Some of the specimens display thinner, second-order ridges on the margin of the hypichnion

Synonymy list
1869     Rusophycus dispar n. sp. — Linnarsson , pp. 353-356
1977     Rusophycus dispar Linnarsson, 1869 — Jensen , pp. 81 , fig. 54-57
2012     Rusophycus dispar Linnarsson, 1869 — Stachasz , pp. 239 , fig. 2A-D
2015     Cruziana dispar — Aceñolaza, Heredia & Carlorosi
Selection of related publications
Rydell, J., Hammarlund, J., Seilacher, A. 2001. Trace fossil associations in the Swedish Mickwitzia sandstone (Lower Cambrian): Did trilobites really hunt for worms?. GFF 123, 4, 247-250. DOI:10.1080/11035890101234247
Jensen, S. 1997. Trace fossils from the Lower Cambrian Mickwitzia sandstone, south-central Sweden. Fossils and Strata 42, 1-110.