USNM806c, Cerros de los Monos, El Antimonio, Sonora (Permian of Mexico)

Where: Sonora, Mexico (30.8° N, 112.6° W: paleocoordinates 11.7° N, 40.3° W)

• coordinate estimated from map

• local area-level geographic resolution

When: Antimonio Formation, Wordian (268.8 - 265.1 Ma)

• "Monos Beds"; Composita zone is second-highest in succession

Environment/lithology: marine; shelly/skeletal, cherty/siliceous limestone

• 20 feet of massive, impure limestone with considerable chert and quantities of silicified fossils

Size class: macrofossils

Preservation: replaced with silica

Primary reference: G. A. Cooper, C.O. Dunbar, H. Duncan, A.K. Miller, and J.B. Knight. 1953. Permian fauna at El Antimonio, western Sonora, Mexico. Smithsonian Miscellaneous Collections 119(2):1-111 [D. Bottjer/M. Clapham/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 40811: authorized by David Bottjer, entered by Matthew Clapham on 01.07.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

Strophomenata
 Productida - Productellidae
Liosotella rugosa Cooper 1953
Marginifera "sp. 2" Waagen 1884
Rhynchonellata
 Athyridida - Athyrididae
Composita grandis Cooper 1953
 Terebratulida - Notothyrididae
 Spiriferinida - Reticulariinidae
"Spiriferellina sonorensis" = Reticulariina sonorensis
"Spiriferellina sonorensis" = Reticulariina sonorensis Cooper 1953
 Rhynchonellida - Wellerellidae
Wellerella lemasi Cooper 1953
 Rhynchonellida - Rhynchoporidae