Sierra del Alamo, Antimonio Formation, Section 3 (Triassic of Mexico)

Where: Sonora, Mexico (30.7° N, 112.6° W: paleocoordinates 12.0° N, 53.9° W)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Lower Member (Antimonio Formation), Norian (228.0 - 208.5 Ma)

• based on ammonites

• group of beds-level stratigraphic resolution

Environment/lithology: open shallow subtidal; gray limestone and fine-grained sandstone

• dark-gray impure limestones, that alternate with shale, siltstone and fine-grained sandstone

Size class: macrofossils

Preservation: cast, mold/impression

Collection methods: bulk, surface (float),

Primary reference: G. D. Stanley, Jr., C. Gonzalez-Leon, M. R. Sandy, B. Senowbari-Daryan, P. Doyle, M. Tamura, and D. H. Erwin. 1994. Upper Triassic invertebrates from the Antimonio Formation, Sonora, Mexico. The Paleontological Society Memoir 36:1-33 [M. Aberhan/S. Nurnberg/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 39172: authorized by Martin Aberhan, entered by Sabine N├╝rnberg on 23.05.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

Bivalvia
 Cardiida - Palaeocarditidae
 Trigoniida - Trigoniidae
Myophorigonia jaworskii Steinmann 1929 clam
Myophorigonia salasi Alencaster 1961 clam
Gastropoda
 Trochonematoidea - Trochonematidae
Guidonia cf. parvula Haas 1953 snail
Guidonia cf. intermedia Haas 1953 snail
 Trochonematoidea - Lophospiridae
? Worthenia sp. de Koninck 1883 snail
 Hypsogastropoda - Coelostylinidae
Omphaloptychia sp. von Ammon 1893 snail
 Allogastropoda - Gordenellidae
Promathildia sp. Andreae 1887 snail
 Murchisoniina - Gosseletinidae
Glabrocingulum sp. Thomas 1940 snail
 Murchisoniina - Loxonematidae
 Seguenzioidea - Eucycloscalidae
Eucycloscala subbisertus d'Orbigny 1849 snail
Rhynchonellata
 Terebratulida -
Pseudorhaetina antimoniensis n. sp. Sandy 1994
 Spiriferinida - Spondylospiridae
Hydrozoa
 Milleporina - Heterastrididae
Heterastridium conglobatum Reuss 1854 fire coral
Anthozoa
 Scleractinia - Margarophylliidae
Distichomeandra austriaca Frech 1890 stony coral
 Scleractinia - Alpinophylliidae
Alpinophyllia flexuosa Roniewicz 1989 stony coral
Disjectoporidae
  - Disjectoporidae
Pamiropora sonorensis n. sp. Stanley 1994