Palaeopascichnus delicatus
palij, 1976

Palaeopascichnus from the Wonoka Formation, South Australia. Specimen SAM P36855.

Palaeopascichnus is an unusual fossil found in shallow marine depositional environments worldwide during the latest Ediacaran Period. It is composed of a series of progressively expanding 'sausage-shaped' units, which often branch after reaching a certain size.

It has been variously interpreted as a trace fossil (Palij, 1976), a bedding-parallel stromatolite (Runnegar, 1995), a brown alga (Haines, 2000) and a giant protozoan (Seilacher et al., 2003). A recent paper assessing the growth and development in Palaeopascichnus arguably described it as a body fossil of a protozoan organism (Antcliffe et al., 2011).

Described from:
Flinders Ranges, South Australia
Newfoundland, Canada
Khorbusuonka River, Siberia, Russia

Key references:
Palij, 1976
Runnegar, 1995
Haines, 2000
Jensen et al., 2003
Seilacher et al., 2003
Antcliffe et al., 2011

Palij, V.M., Posti, E. & Fedonkin, M.A., 1979. Soft-bodied Metazoa and trace fossils of Vendian and Lower Cambrian. In Upper Precambrian and Cambrian Paleontology of East-European Platform. Keller, B.M. & Rozanov, A.Yu., eds, Moscow, Nauka, 49-82.