Where: Sonora, Mexico (30.8° N, 112.6° W)

• Paleocoordinates: 16.2° N, 38.2° W (Wright 2013)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Antimonio Formation, Wordian (266.9 - 264.3 Ma)

• "Monos Beds"; Spiriferellina Zone is uppermost in the succession

Environment/lithology: marine; lithified, blue, cherty/siliceous limestone

Size class: macrofossils

Preservation: replaced with silica

Collected by G.A. Cooper in 1943; reposited in the USNM

Primary reference: A. K. Miller. 1945. A Permian ammonoid from Sonora. Journal of Paleontology 19:22 [M. Clapham/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 129556: authorized by Matthew Clapham, entered by Matthew Clapham on 24.06.2012

Creative Commons license: CC0 (CC0)