TY - JOUR
T1 - Palaeobiological significance of Plagiogmus arcuatus from the lower Cambrian of central Australia
AU - Heys, George Rowland
AU - McIlroy, D
PY - 1997
Y1 - 1997
N2 - The Cambrian trace fossil Plagiogmus is the floor of a backfilled burrow which is common in the deltaic sediments of the Arumbera Sandstone in central Australia. The Plagiogmus forming organism/s was/were connected to the surface by a siphon that formed a longitudinal furrow. Collapse associated with the movement of the siphon through the sediment may have produced a variety of trace fossil morphologies similar to the ichnogenera Gordia, Cochlichnus and Taphrhelminthopsis. Other parts of the Plagiogmus burrow may be compared with Olivellites, Aulichnites, Laminites, Climactichnites and Psammichnites ispp. The distinctive transverse bars of the Plagiogmus structure are interpreted as being produced by a posterior sucker used by the animal during locomotion. It is interpreted that the burrow fill was composed solely of feeding wastes and not the spoils of tunnelling. The laminae within the backfill are not related to the transverse bars. Bilobed burrows overlying the Plagiogmus component are related to the presence of a siphon that we interpret to have been used in surface deposit feeding. The biological affinities of the Plagiogmus-forming animal remain obscure, but it was probably vermiform and shared characters with the Mollusca, Annelida, Hirundinea and/or some echinuran worms.
AB - The Cambrian trace fossil Plagiogmus is the floor of a backfilled burrow which is common in the deltaic sediments of the Arumbera Sandstone in central Australia. The Plagiogmus forming organism/s was/were connected to the surface by a siphon that formed a longitudinal furrow. Collapse associated with the movement of the siphon through the sediment may have produced a variety of trace fossil morphologies similar to the ichnogenera Gordia, Cochlichnus and Taphrhelminthopsis. Other parts of the Plagiogmus burrow may be compared with Olivellites, Aulichnites, Laminites, Climactichnites and Psammichnites ispp. The distinctive transverse bars of the Plagiogmus structure are interpreted as being produced by a posterior sucker used by the animal during locomotion. It is interpreted that the burrow fill was composed solely of feeding wastes and not the spoils of tunnelling. The laminae within the backfill are not related to the transverse bars. Bilobed burrows overlying the Plagiogmus component are related to the presence of a siphon that we interpret to have been used in surface deposit feeding. The biological affinities of the Plagiogmus-forming animal remain obscure, but it was probably vermiform and shared characters with the Mollusca, Annelida, Hirundinea and/or some echinuran worms.
U2 - 10.1080/03115519708619171
DO - 10.1080/03115519708619171
M3 - Comment/debate
VL - 21
SP - 161
EP - 178
JO - Alcheringa: an Australasian journal of palaeontology
JF - Alcheringa: an Australasian journal of palaeontology
SN - 0311-5518
IS - 3
ER -