Powder Wash (Upper) (Eocene of the United States)

Also known as Powder Springs

Where: Uintah County, Utah (40.2° N, 109.9° W: paleocoordinates 44.2° N, 96.4° W)

• coordinate based on political unit

• small collection-level geographic resolution

When: Douglas Creek Member (Green River Formation), Bridgerian (50.3 - 46.2 Ma)

• group of beds-level stratigraphic resolution

Environment/lithology: channel lag; sandstone

• the "association of hard, dense, bony elements in a sandstone suggests a lag deposit within a channel or splay... [perhaps] a small meandering stream channel, a lake-margin (deltaic) distributary channel, or the basal portion of a crevasse splay" (Gunnell and Bartels 1999)
• "a uniformly muddy, fine-grained sublitharenite" (Gunnell and Bartels 1999)

Size classes: macrofossils, mesofossils

Primary reference: L. Krishtalka and R. K. Stucky. 1984. Middle Eocene marsupials (Mammalia) from northeastern Utah and the mammalian fauna from Powder Wash. Annals of Carnegie Museum 53(2):31-46 [J. Alroy/J. Alroy/M. Uhen]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 16396: authorized by John Alroy, entered by John Alroy on 18.02.1993, edited by Patricia Holroyd

Creative Commons license: CC BY (attribution)

Taxonomic list

• sec 8 T 7S R 25E: Van Houten 1945
same as the "Green River" fauna of Burke 1935 and Kay 1957
according to Remy 1992 there is an Ar-Ar date of 47.2 Ma on the "curly tuff... between the S1 marker unit and the Magohany oil shale bed" (S1 unit is lower); because the fauna is from "82 m below" the shale and the date is interpreted by Remy as Uintan, I assume it is too young for use as a calibration point
"Class 1" reliability K-Ar date of 44.8 (= 46.0) +/- 0.9 Ma (Mauger 1977) for the Wavy Tuff is definitely too young for use as the tuff is 20 ft above the Mahogany Oil Shale; Wavy Tuff redated at 42.3 +/- 2.0 (FT on zircon) by Bryant et al. 1989
original list repeated almost without modification by Gunnell and Bartels 1999
Black and Sutton list the following: Thisbemys corrugatus "Leptotomus bridgerensis"
falls in the Parachute Creek Mbr. sensu Roehloer 1992
early Bridgerian
the record of Apatemys hendryi reported by Robinson 1966b is omitted without comment by K & S
Reptilia
 Crocodylia - Planocraniidae
"Pristichampsus vorax" = Boverisuchus vorax5
"Pristichampsus vorax" = Boverisuchus vorax5 Troxell 1925 crocodilian
 Crocodylia -
Procaimanoidea kayi5 Mook 1941 crocodilian
 Squamata -
Booidea indet.5 Gray 1825 snake
 Squamata - Xantusiidae
Palaeoxantusia sp.5 Hecht 1956 night lizard
spelled "Paleoxantusia"
 Squamata -
Saniwa sp.5 Leidy 1870 squamates
 Squamata - Anguidae
Xestops vagans5 Marsh 1872 squamates
Glyptosaurus sylvestris5 Marsh 1871 squamates
Eodiploglossus borealis5 Gauthier 1982 squamates
 Squamata - Iguanidae
Parasauromalus sp.5 Gilmore 1928 squamates
Parasauromalus olseni5 Gilmore 1928 squamates
 Squamata -
Tinosaurus stenodon5 Marsh 1872 squamates
 Testudines - Pantestudinidae
Hadrianus sp.5 Cope 1872 turtle
 Testudines - Geoemydidae
Echmatemys sp.5 Hay 1906 turtle
 Testudines - Trionychidae
Trionychidae indet.5 Gray 1825 softshell turtle
Mammalia
 Theriamorpha - Leptictidae
Palaeictops bridgeri Simpson 1959 eutherian
 Cimolesta - Apatemyidae
Apatemys cf. bellus Marsh 1872 eutherian
Apatemys cf. bellulus Marsh 1872 eutherian
Apatemys cf. rodens Troxell 1923 eutherian
 Cimolesta - Esthonychidae
Trogosus sp. Leidy 1871 tillodont
 Chiroptera - Natalidae
cf. Ageina sp. Russell et al. 1973 funnel-eared bat
a bat
 Condylarthra - Hyopsodontidae
Hyopsodus minusculus3 Leidy 1873 condylarth
Hyopsodus paulus Leidy 1870 condylarth
confirmed by Redline 1997
 Acreodi - Mesonychidae
Mesonychidae indet. Cope 1875 condylarth
 Creodonta - Hyaenodontidae
Sinopa major1 Wortman 1902 creodont
Sinopa rapax1 Leidy 1871 creodont
Proviverroides cf. piercei4 Bown 1982 creodont
Tritemnodon cf. agilis4 Marsh 1872 creodont
 Creodonta -
Limnocyon cf. verus Marsh 1872 creodont
 Theriamorpha -
Miacis cf. parvivorus Cope 1872 placental
 Carnivora - Miacidae
Miacidae indet. Cope 1880 carnivoran
said to be a new genus
Miocyon cf. major1 Matthew 1909 carnivoran
 Theriamorpha -
Procynodictis cf. vulpiceps4 Wortman and Matthew 1899 placental
 Theriamorpha - Viverravidae
Viverravus minutus Wortman 1901 placental
Viverravus sicarius Matthew 1909 placental
Viverravus gracilis Marsh 1872 placental
 Theriamorpha -
? Oodectes sp. Wortman 1901 placental
 Perissodactyla - Palaeotheriidae
Hyracotherium vasacciense Cope 1872 odd-toed ungulate
 Perissodactyla - Hyrachyidae
Hyrachyus modestus Leidy 1870 odd-toed ungulate
 Perissodactyla -
Helaletes nanus Marsh 1871 odd-toed ungulate
 Artiodactyla - Homacodontidae
"Homacodontinae indet." = Homacodontidae, Antiacodon pygmaeus
"Homacodontinae indet." = Homacodontidae Marsh 1849 even-toed ungulate
said to be new
Antiacodon pygmaeus Cope 1872 even-toed ungulate
includes "cf. Neodiacodexis sp." of West 1984 according to Stucky 1998; see also Burke 1969
 Theriamorpha - Geolabididae
Centetodon bembicophagus Lillegraven et al. 1981 placental
Centetodon pulcher Marsh 1872 placental
not listed by Lillegraven et al. 1981
 Theriamorpha - Nyctitheriidae
"Scenopagus priscus" = Nyctitherium priscum, "Talpavus nitidus" = Nyctitherium nitidum, Nyctitherium serotinum
"Scenopagus priscus" = Nyctitherium priscum Marsh 1872 placental
"Talpavus nitidus" = Nyctitherium nitidum Marsh 1872 placental
Nyctitherium serotinum Marsh 1872 placental
described by Krishtalka 1976b
 Theriamorpha - Apternodontidae
Apternodontidae indet.2 Matthew 1910 placental
 Theriamorpha - Sespedectidae
Crypholestes sp.1 Novacek 1980 placental
 Theriamorpha - Pantolestoidae
Pantolestes cf. longicaudus Cope 1872 placental
 Theriamorpha -
Aethomylos simplicidens Novacek 1976 placental
 Rodentia - Sciuravidae
Sciuravidae indet. Miller and Gidley 1918 rodent
Sciuravus eucristadens Burke 1937 rodent
includes "Microparamys sp. C" of Wood 1962: see Dawson 1968, Korth 1984
Pauromys sp. Troxell 1923 rodent
 Rodentia - Ischyromyidae
Microparamys minutus Wilson 1937 rodent
Paramys delicatus Leidy 1871 rodent
Pseudotomus sp.6 Cope 1872 rodent
 Primates - Notharctidae
Smilodectes gracilis Marsh 1871 primate
Notharctus cf. tenebrosus Leidy 1870 primate
sensu Gingerich 1979a
 Primates - Omomyidae
Omomys lloydi n. sp. Gazin 1958 tarsier
see Gazin 1958a
Omomys carteri Leidy 1869 tarsier
Uintanius ameghini Wortman 1904 tarsier
includes one specimen of Utahia kayi: Szalay 1976
Utahia kayi n. sp. Gazin 1958 tarsier
see Gazin 1958a
Anaptomorphus aemulus Cope 1872 tarsier
 Primates - Microsyopidae
Microsyops sp. Leidy 1872 primate
Uintasorex cf. parvulus Matthew 1909 primate
 Proteutheria - Palaeoryctidae
Palaeoryctinae indet. Winge 1917 eutherian
 Theriamorpha - Peradectidae
Peradectes chesteri Gazin 1952 marsupial
Armintodelphys dawsoni Krishtalka and Stucky 1983 marsupial
 Theriamorpha - Herpetotheriidae
"Copedelphys innominata" = Herpetotherium innominatum1 Simpson 1928 marsupial
Herpetotherium marsupium1 Troxell 1923 marsupial
Scenopagus edenensis
  -
Scenopagus edenensis McGrew et al. 1959