LSJU loc. FL 38, Cottonwood Mountains (Carboniferous of the United States)

Where: Inyo County, California (36.8° N, 117.5° W: paleocoordinates 3.0° N, 46.9° W)

• coordinate estimated from map

When: Rest Spring Formation, Arnsbergian (327.0 - 323.7 Ma)

• McAllister (1952) and Gordon (1964) say this is the uppermost 10 ft and probably lower 5 ft of Rest Spring Shale

•If Perdido group, this would be the Mexican Spring Formation of Stevens et al., 1996

•Titus (2000) says this is lower Rest Spring Shale, but doesn't give any evidence. Says "the formational contact between the Rest Spring Shale and the underlying Mexican Spring Formation essentially coincides with the Pendleian-Arnsbergian boundary" making this Arnsbergian if Rest Spring, or Pendleian if Mexican Spring.

Environment/lithology: marine; fine-grained, gray limestone and calcareous siltstone

• In the Quartz Spring area the Early Mississippian Tin Mountain Limestone is overlain by a sequence of varied beds that consists of calcareous siltstone, sand- stone, conglomerate and interbedded chert, limestone, silty limestone, and siltstone having some shale. These constitute the Perdido Formation of McAllister (1952, p. 22-25), approximately 610 feet thick in its composite type section south of Perdido Canyon and south of Rest Spring.The topmost bed of this formation, a dark-gray fine-grained limestone, 6 to 12 inches thick, is crowded with fossils, mostly Cravenoceras hesperium Miller and Furnish. Four to five feet of very soft shale, grayish red to purplish gray, separate it from the gray locally sandy limestone below that carries productids, spirifers, and other brachiopods.

Size class: macrofossils

Reposited in the CAS

Collection methods: surface (float),

Primary reference: M. Gordon, Jr. 1964. California Carboniferous cephalopods. United States Geological Survey Professional Paper 483-A:A1-A27 [J. Marcot/J. Marcot/J. Marcot]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 217143: authorized by Jonathan Marcot, entered by Jonathan Marcot on 26.01.2021

Creative Commons license: CC BY (attribution)

Taxonomic list

 Pseudorthocerida - Pseudorthoceratidae
 Bactritida - Bactritidae
 Nautilida - Scyphoceratidae
Scyphoceras cf. cessator Hall and Whitfield 1877 nautiloid
 Nautilida - Liroceratidae
? Liroceras sp. Teichert 1940 nautiloid
 Goniatitida - Girtyoceratidae
Eumorphoceras paucinodum n. sp. Gordon 1964 ammonite
 Goniatitida - Glaphyritidae
"Cravenoceras inyoense" = Fayettevillea inyoense, "Cravenoceras hesperium" = Eosyngastrioceras hesperium
"Cravenoceras inyoense" = Fayettevillea inyoense Gordon 1964 ammonite
"Cravenoceras hesperium" = Eosyngastrioceras hesperium Miller and Furnish 1940 ammonite
 Goniatitida - Eogonioloboceratidae
"Anthracoceras macallisteri n. sp." = Arcanoceras macallisteri
"Anthracoceras macallisteri n. sp." = Arcanoceras macallisteri Gordon 1964 ammonite