Ptyagnostus atavus or Leiopyge calva Zone (Cambrian of the United States)

Where: Utah (38.9° N, 113.4° W: paleocoordinates 4.1° S, 92.0° W)

• coordinate based on political unit

• basin-level geographic resolution

When: Ptyagnostus atavus or Leiopyge trilobite zone, Marjum Limestone Formation, Marjumian (513.0 - 498.5 Ma)

• "Ptyagnostus atavus or Leiopyge calva Zone" (Topazan, which is still Marjumian here; PJW)

Environment/lithology: offshore ramp; burrowed, peloidal packstone

• "carbonate packstone, w/ f-p congl., 30-50 cm thick, bioturbation, peloidal mud. subtidal, open shelf, upper slopes of a ramp, BA2 or possibly 4

Size classes: macrofossils, mesofossils

Primary reference: A. J. Rowell and N. E. Caruso. 1985. The evolutionary significance of Nisusia sulcata, an early articulate brachiopod. Journal of Paleontology 59(5):1227-1242 [A. Hendy/A. Hendy] more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 262: authorized by Jack Sepkoski, entered by Mike Sommers on 20.11.1998