83RB9, south flank of Limestone Mountain (Devonian of the United States)

Where: Medfra County, Alaska (63.3° N, 154.5° W: paleocoordinates 2.5° N, 46.0° W)

• coordinate stated in text

• outcrop-level geographic resolution

When: Polygnathus dehiscens conodont zone, Limestone Mountain Formation, Early/Lower Emsian (409.1 - 402.5 Ma)

• On the basis of regional stratigraphic correlations and faunal composition, the host beds appear to be slightly younger than the earliest Emsian (Polygnathus dehiscens Zone) Soda Creek Limestone (Blodgett et al., 2000).

•(This would be Polygantuhs gronbergi/P. excavatus zone, or 406-403.5 Ma on Gradstein et al.)

•Note also that "Limestone Mountain" is an informal name.

• bed-level stratigraphic resolution

Environment/lithology: limestone

• Transitional biofacies from the more open-marine environment below into the restricted lagoonal facies above.

•The dominance of the fauna by a highly diverse assemblage of gastropods, together with the abundance of the tubular stromatoporoid genus Amphipora in underlying and overlying strata, indicates a relatively shallow-water (shallow part of the photic zone), inner carbonate platform environment. (Fryda & Blodgett 2004:111)

• 1.5 m thick, silicified, richly fossiliferous rubble zone in an unnamed Devonian limestone unit; eurekaensis / delta conodont zones (Fryda & Blodgett 2004).

Size class: macrofossils

Preservation: replaced with silica

Reposited in the USNM

• Cobbled together from multiple taxonomy papers

Primary reference: R. B. Blodgett and D. M. Rohr. 1989. Two new Devonian spine-bearing pleurotomariacean gastropod genera from Alaska. Journal of Paleontology 63(1):47-52 [P. Wagner/P. Wagner/P. Wagner]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 49107: authorized by Pete Wagner, entered by Pete Wagner on 08.04.2005, edited by Sarah Kolbe

Creative Commons license: CC BY (attribution)

Taxonomic list

Demospongiae
 Ceractinomorpha -
Medfraspongia tubulara5 Rigby et al. 2009 demosponge
Stromatoporoidea
 Amphiporida - Amphiporidae
Amphipora sp.4 Schulz 1883 stromatoporoid sponge
Anthozoa
 Rugosa -
Rugosa indet.5 horn coral
 Tabulata -
Tabulata indet.5 tabulate coral
Ostracoda
 Palaeocopida - Beyrichiidae
Beyrichia (Scabribeyrichia) churkini ostracod
Berdan & Copeland 1973
 Palaeocopida -
Nezamyslia aff. jucunda ostracod
Polenova 1974
? Scaphina sp. ostracod
 Palaeocopida - Miltonellidae
? Libumella sp. Rozhdestvenskaya 1959 ostracod
 Leperditicopida - Moelleritiidae
? Eomoelleritia sp. Abushik 1972 ostracod
Scaphopoda
  -
Scaphopoda indet.5 Bronn 1862 tusk shell
Bivalvia
  -
Bivalvia indet.5 Linnaeus 1758 clam
Gastropoda
 Murchisoniina - Soleniscidae
Nanochilina gubanovi n. sp.4, Alaskacirrus bandeli n. gen. n. sp.2
Nanochilina gubanovi n. sp.4 Frýda and Blodgett 2004 snail
Alaskacirrus bandeli n. gen. n. sp.2 Frýda and Blodgett 1998 snail
 Murchisoniina - Palaeozygopleuridae
Medfrazyga clauticae n. gen. n. sp.4, "Palaeozygopleura (Rhenozyga) reifenstuhli n. sp." = Rhenozyga reifenstuhli4
Medfrazyga clauticae n. gen. n. sp.4 Frýda and Blodgett 2004 snail
"Palaeozygopleura (Rhenozyga) reifenstuhli n. sp." = Rhenozyga reifenstuhli4 Frýda and Blodgett 2004 snail
 Murchisoniina - Porcelliidae
"Quadricarina (? Quadricarina) noklebergi n. sp." = Quadricarina noklebergi4, Alaskiella medfraensis n. gen. n. sp.2
"Quadricarina (? Quadricarina) noklebergi n. sp." = Quadricarina noklebergi4 Frýda and Blodgett 2004 snail
Alaskiella medfraensis n. gen. n. sp.2 Frýda and Blodgett 1998 snail
 Murchisoniina - Gosseletinidae
Chlupacispira spinosa n. gen. n. sp., Arctozone cooki n. gen. n. sp.4, Balbinipleura krawczynskii n. sp.4
Chlupacispira spinosa n. gen. n. sp. Blodgett and Rohr 1989 snail
Arctozone cooki n. gen. n. sp.4 Frýda and Blodgett 2004 snail
Balbinipleura krawczynskii n. sp.4 Frýda and Blodgett 2004 snail
 Murchisoniina - Murchisoniidae
Farewellia heidelbergerae n. gen. n. sp.4
Farewellia heidelbergerae n. gen. n. sp.4 Frýda and Blodgett 2004 snail
 Heterobranchia - Kuskokwimiidae
Kuskokwimia moorei n. gen. n. sp.3
Kuskokwimia moorei n. gen. n. sp.3 Frýda and Blodgett 2001 snail
 Euomphalina - Pseudophoridae
Decorospira lepaini n. sp.4 Frýda and Blodgett 2004 snail
? Decorospira minutula n. sp.4 Frýda and Blodgett 2004 snail
 Euomphalina - Euomphalidae
Euomphalopterus sp.2, "Straparollus (Eleutherospira) medfraensis" = Eleutherospira medfraensis1
Euomphalopterus sp.2 Roemer 1876 snail
"Straparollus (Eleutherospira) medfraensis" = Eleutherospira medfraensis1 Blodgett and Johnson 1992 snail
Cephalopoda
  -
Cephalopoda indet.5 Cuvier 1797
 Ammonoidea -
Ammonoidea indet.5 Zittel 1884 ammonite
 Lophophorata -
Tentaculitida indet.5 Ljaschenko 1955
Brachiopoda
  -
Brachiopoda indet.5 Cuvier 1805