Cottonwood Canyon (FMNH excavation) (Devonian of the United States)

Where: Wyoming (44.9° N, 108.1° W: paleocoordinates 19.1° S, 54.1° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Pedavis pesavis conodont zone, "Cottonwood Canyon" Member (Beartooth Butte Formation), Lochkovian (419.2 - 410.8 Ma)

• Vertebrate biostratigraphy (Elliot and Ilyes, 1996) indicates that the Cottonwood Canyon section is Pragian whereas the type section at Beartooth Butte is Emsian. PJW: Bleick & Coultier (2000) put this in the Pedavis pesavis zone, which is uppermost Lockhovian. I have put this in an informal "Cottonwood Canyon" member because it seems probable that this part of the Beartooth Butte will be separated into a unique formation.

• group of beds-level stratigraphic resolution

Environment/lithology: estuary or bay; lithified siliciclastic sediments

• Stable oxygen and isotope data (Poulson in Fiorillo, 2000) indicate that the Beartooth Butte Formation was deposited in an estuarine environment, with the Cottonwood Canyon section being slightly less saline than the type section.

Size class: macrofossils

Preservation: adpression

Collected by R.H. Denison, E.S. Richarsdon in 1962; reposited in the FMNH

Primary reference: E. N. Kjellesvig-Waering. 1986. A restudy of the fossil Scorpionida of the world. Palaeontographica Americana 55:1-287 [M. Clapham/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 153534: authorized by Matthew Clapham, entered by Matthew Clapham on 26.12.2013, edited by Pete Wagner

Creative Commons license: CC BY (attribution)

Taxonomic list

 Scorpiones - Acanthoscorpionidae
Acanthoscorpio mucronatus n. gen. n. sp. Kjellesvig-Waering 1986 scorpion
FMNH PE 6177ab
 Scorpiones - Praearcturidae
Praearcturus sp. Woodward 1871 scorpion
FMNH PE 26080B
 Scorpiones - Proscorpiidae
Hydroscorpius denisoni n. gen. n. sp.
Hydroscorpius denisoni n. gen. n. sp. Kjellesvig-Waering 1986 scorpion
FMNH PE 6176
 Scorpiones - Branchioscorpionidae
Branchioscorpio richardsoni n. gen. n. sp. Kjellesvig-Waering 1986 scorpion
FMNH PE 6176a,b
 Heterostraci - Protaspidae
Protaspis brevispina2 jawless fish
Protaspis mcgrewi2 jawless fish
 Heterostraci - Cardipeltidae
Cardipeltis bryanti2 Denison 1966 jawless fish
 Pteraspidiformes - Pteraspididae
"Protaspis (Cosmaspis) transversa n. sp." = Cosmaspis transversa1, Lampraspis tuberculata n. sp.1
"Protaspis (Cosmaspis) transversa n. sp." = Cosmaspis transversa1 Denison 1970 jawless fish
Lampraspis tuberculata n. sp.1 Denison 1970 jawless fish
 Arthrodira - Actinolepidae
Aethaspis sp.2 Denison 1958 armour-plated fish
Simblaspis sp.2 Denison 1958 armour-plated fish
 Dipnoi - Uranolophidae
Uranolophus wyomingensis2 Denison 1968 lungfish
 Cephalaspidiens - Cephalaspidae
Cephalaspis sp.2 Agassiz 1843