Discovery Site (Eocene of the United States)

Also known as SC-29

Where: Park County, Wyoming (44.8° N, 109.0° W: paleocoordinates 49.4° N, 92.3° W)

• coordinate stated in text

• small collection-level geographic resolution

When: Willwood Formation, Early/Lower Eocene (55.8 - 48.6 Ma)

• said to be both late Clarkforkian and Eocene

• group of beds-level stratigraphic resolution

Environment/lithology: wet floodplain; lithified, lenticular, brown wackestone

• the "distribution of limestone lenses and the fauna of lens J suggest accumulation in a hollow tree trunk" on a floodplain, not in a lacustrine context, while "the Ectocion limestone [at SC-29] involved slow burial in current winnowed quartz and carbonate sand [in moving water]"
• lens J "is a mottled micritic muddy limestone (wackestone) including gastropod shell fragments, plant debris, and vertebrate bone" that is "brown in unweathered hand specimens"

Size classes: macrofossils, mesofossils

Preservation: replaced with calcite, bone collector

Collected by P. D. Gingerich in 1975; reposited in the UMMP

Collection methods: bulk, quarrying, chemical,

• "The entire lens J fauna [at SC-29] was recovered from a mass of freshwater limestone occupying a volume of approximately 2,000 c3 and weighing an estimated 5 kg" and vertebrates fossil were recovered by "dissolution of the limestone in dilute formic acid (10%)"

Primary reference: P. D. Gingerich. 1987. Early Eocene bats (Mammalia, Chiroptera) and other vertebrates in freshwater limestones of the Willlwood Formation, Clark's Fork Basin, Wyoming. Contributions from the Museum of Paleontology, University of Michigan 27(11):275-320 [J. Alroy/J. Alroy/J. Alroy]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 15081: authorized by John Alroy, entered by John Alroy on 18.02.1993, edited by Will Clyde and Patricia Holroyd

Creative Commons license: CC BY (attribution)

Taxonomic list

• the entire original list applies only to lens J
unclassified
  -
Gastropoda
 Stylommatophora - Oreohelicidae
Oreohelix megarche Cockerell and Henderson 1912 mountain snail
 Stylommatophora - Sagdidae
cf. Microphysula sp. Cockerell 1926 slug
 Stylommatophora - Helicidae
"Hendersonia evanstonensis" = Helix evanstonensis, "Grangerella sinclairi" = Gastrodonta evanstonensis sinclairi
"Hendersonia evanstonensis" = Helix evanstonensis White 1878 slug
"Grangerella sinclairi" = Gastrodonta evanstonensis sinclairi Cockerell 1912 slug
 Stylommatophora - Pupillidae
cf. Albertanella minuta Russell 1931 slug
 Stylommatophora - Pyramidulidae
"Discus ralstonensis" = Pyramidula ralstonensis
"Discus ralstonensis" = Pyramidula ralstonensis Cockerell 1914 slug
 Heterostropha - Acteonidae
"cf. Pupilla sp." = Pupa (Pupilla)
"cf. Pupilla sp." = Pupa (Pupilla) Leach 1828 snail
Amphibia
 Caudata - Urodela
Urodela indet. salamander
isolated vertebrae
 Salientia -
Anura indet. frog
distal humerus
Aves
 Telluraves -
Calcardea junnei n. gen. n. sp.
Calcardea junnei n. gen. n. sp. Gingerich 1987 bird
Reptilia
 Testudines - Pantrionychidae
Plastomenus sp.2 Cope 1873 turtle
 Squamata -
Varanoidea indet. Gray 1827 squamates
Mammalia
 Chiroptera - Icaronycteridae
cf. Icaronycteris sp. Jepsen 1966 bat
a bat
 Theriamorpha - Viverravidae
Viverravus laytoni1 Gingerich and Winkler 1985 placental
Didymictis proteus6 Polly 1997 placental
 Theriamorpha - Nyctitheriidae
Limaconyssus habrus n. gen. n. sp. Gingerich 1987 placental
cf. Leptacodon sp. Matthew and Granger 1921 placental
Wyonycteris chalix n. gen. n. sp. Gingerich 1987 placental
thought by Gingerich to be a bat, but by Hand et al. 1994 to be a non-chiropteran archontan of unclear affinities
"Leptacodon rosei" = Plagioctenodon rosei Gingerich 1987 placental
Plagioctenodon thewisseni5 Manz and Bloch 2015 placental
 Primates - Carpolestidae
Carpolestes simpsoni n. sp.3 Bloch and Gingerich 1998 primate
 Primates - Micromomyidae
Tinimomys graybulliensis Szalay 1974 primate
 Dermoptera -
cf. Worlandia sp. Bown and Rose 1979 colugo
 Theriamorpha - Peradectidae
Peradectes protinnominatus4 McKenna 1960 marsupial
 Multituberculata - Neoplagiaulacidae
Ectypodus powelli Jepsen 1940 multituberculate
Boysia
  -
"cf. Grangerella phenacodorum" = Boysia phenacodorum
"cf. Grangerella phenacodorum" = Boysia phenacodorum Cockerell 1914