Rusophycus

Rusophycus is a trace fossil allied to Cruziana[1]. Rusophycus is the resting trace, recording the outline of the tracemaker; Cruziana is made when the organism moved.[2] Both are typically associated with trilobites but can also made by other arthropods.[3]

Rusophycus is known from sediments dating right to the base of the Cambrian (542 million years ago), long before the earliest trilobite fossils, and from the Triassic (after the Permian extinction of trilobites), indicating that other producers could make the trace.[4]

References

  1. ^ Baldwin, C. T. (1977). "Rusophycus morgati: an asaphid produced trace fossil from the Cambro-Ordovician of Brittany and Northwest Spain". Palaeontology 51: 411–425. 
  2. ^ Garlock, T. L.; Isaacson, P. E. (1977). "An occurrence of a Cruziana population in the Moyer Ridge Member of the Bloomsberg Formation (Late Silurian)-Snyder County, Pennsylvania.". Palaeontology (Journal of Paleontology, Vol. 51, No. 2) 51 (2): 282–287. JSTOR 1303607 
  3. ^ Woolfe, K. (1990). "Trace fossils as paleoenvironmental indicators in the Taylor group (Devonian) of Antarctica". Palaeogeography, Palaeoclimatology, Palaeoecology 80 (3–4): 301–310. doi:10.1016/0031-0182(90)90139-X.  edit
  4. ^ Donovan, S. K. (2010). "Cruziana and Rusophycus: trace fossils produced by trilobites … in some cases?". Lethaia 43 (2): 283–284. doi:10.1111/j.1502-3931.2009.00208.x.  edit