Bottom Rock, 600 meters ESE of Trilobite Rock (Cambrian of New Zealand)

Also known as 300 meters S of Cobb River

Where: Nelson, New Zealand (41.0° S, 173.0° E: paleocoordinates 41.0° S, 173.0° E)

• outcrop-level geographic resolution

When: Lejopyge laevigata trilobite zone, Tasman Formation, Boomerangian (504.0 - 501.0 Ma)

• The limestone lense is approximately 10 meters thick and has presence of numerous trilobite exuviae. The Tuarangia paparua are most readily collected four to five meters above the base of the limestone lense.

•Originally given a minimum age of Merioneth. However, Mackinnon (1985) gives the age as late Middle Cambrian, and it is placed within the early Boomerangian of the Australian scale. That correlates with Menevian (PJW).

•“Their correlations suggest an age for Trilobite Rock that is within the range of the Ptychagnostus cassis Subzone of the Leiopyge laevigata Zone (i.e., toward the upper limit of the Bolaspidella Zone of North America).”

• bed-level stratigraphic resolution

Environment/lithology: lithified limestone

• limestone lense; internally fragmented as if deposited by some form of sediment gravity flow. Angluar micritic intraclasts set in a micritic matrix

Size classes: macrofossils, microfossils

Preservation: original phosphate

Collection methods: chemical,

• Original shell mineralogy preserved for inarticulates. Molluscs, trilobites, etc. not described.

Primary reference: D. I. Mackinnon. 1982. Tuarangia paparua n. gen. and n. sp., a Late Middle Cambrian pelecypod from New Zealand. Journal of Paleontology 56(3):589-598 [M. Patzkowsky/P. Borkow/J. Alroy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 49850: authorized by Pete Wagner, entered by Pete Wagner on 28.04.2005

Creative Commons license: CC BY (attribution)

Taxonomic list

• Molluscs from adjacent Trilobite Rock described in MacKinnon (1982, 1985)

•Henderson & MacKinnon (1981: Alcheringa) give the inarticulate brachiopods.

Rostroconchia
 Tuarangiida - Tuarangiidae
Tuarangia paparua MacKinnon 1982
Lingulata
 Lingulida - Acrothelidae
Acrothele sp. Linnarsson 1876
 Lingulida - Obolidae
Lingulella sp. Salter 1866
 Acrotretida - Acrotretidae
Amictocracens teres n. gen. n. sp., Treptotreta jucunda n. gen. n. sp., Picnotreta debilis n. gen. n. sp., Stilpnotreta magna n. gen. n. sp., Linnarssonia tumida n. sp., Anabolotreta tegula
Amictocracens teres n. gen. n. sp.
Treptotreta jucunda n. gen. n. sp. Henderson and MacKinnon 1981
Picnotreta debilis n. gen. n. sp. Henderson and MacKinnon 1981
Stilpnotreta magna n. gen. n. sp. Henderson and MacKinnon 1981
Anabolotreta tegula
Rowell & Henderson