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
 Testudines - Trionychidae
Trionychidae indet.5 Gray 1825 softshell turtle
 Testudines - Pantestudinidae
Hadrianus sp.5 Cope 1872 turtle
 Testudines - Pangeoemydidae
Echmatemys sp.5 Hay 1906 turtle
 Crocodylia - Alligatoridae
Procaimanoidea kayi5 Mook 1941 crocodilian
 Crocodylia - Planocraniidae
"Pristichampsus vorax" = Boverisuchus vorax5
"Pristichampsus vorax" = Boverisuchus vorax5 Troxell 1925 crocodilian
 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
Booidea indet.5 Gray 1825 snake
 Squamata - Xantusiidae
Palaeoxantusia sp.5 Hecht 1956 night lizard
spelled "Paleoxantusia"
Mammalia
 Primates - Microsyopidae
Uintasorex cf. parvulus Matthew 1909 primate
Microsyops sp. Leidy 1872 primate
 Primates - Omomyidae
Anaptomorphus aemulus Cope 1872 tarsier
Omomys lloydi n. sp. Gazin 1958 tarsier
see Gazin 1958a
Omomys carteri Leidy 1869 tarsier
Utahia kayi n. sp. Gazin 1958 tarsier
see Gazin 1958a
Uintanius ameghini Wortman 1904 tarsier
includes one specimen of Utahia kayi: Szalay 1976
 Primates - Notharctidae
Notharctus cf. tenebrosus Leidy 1870 primate
sensu Gingerich 1979a
Smilodectes gracilis Marsh 1871 primate
 Cimolesta - Palaeoryctidae
Palaeoryctinae indet. Winge 1917 eutherian
 Cimolesta - Pantolestidae
"Pantolestes cf. longicaudus" = Pantolestes longieundus
"Pantolestes cf. longicaudus" = Pantolestes longieundus Cope 1872 eutherian
 Leptictida - Leptictidae
Palaeictops bridgeri Simpson 1959 eutherian
 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
Pseudotomus sp.6 Cope 1872 rodent
Microparamys minutus Wilson 1937 rodent
Paramys delicatus Leidy 1871 rodent
 Lipotyphla - Geolabididae
Centetodon bembicophagus Lillegraven et al. 1981 placental
Centetodon pulcher Marsh 1872 placental
not listed by Lillegraven et al. 1981
 Perissodactyla - Hyrachyidae
Hyrachyus modestus Leidy 1870 odd-toed ungulate
 Perissodactyla -
Helaletes nanus Marsh 1871 odd-toed ungulate
 Perissodactyla - Palaeotheriidae
Hyracotherium vasacciense Cope 1872 odd-toed ungulate
 Tribosphenida - Nyctitheriidae
Nyctitherium serotinum Marsh 1872 placental
described by Krishtalka 1976b
 Tribosphenida - Apternodontidae
Apternodontidae indet.2 Matthew 1910 placental
 Tribosphenida -
Talpavus nitidus Marsh 1872 placental
 Ferae - Viverravidae
Viverravus gracilis Marsh 1872 placental
Viverravus sicarius Matthew 1909 placental
Viverravus minutus Wortman 1901 placental
 Ferae -
? Oodectes sp. Wortman 1901 placental
 Carnivora - Miacidae
Miacidae indet. Cope 1880 carnivoran
said to be a new genus
Miacis cf. parvivorus Cope 1872 carnivoran
Miocyon cf. major1 Matthew 1909 carnivoran
 Carnivora -
Procynodictis cf. vulpiceps4 Wortman and Matthew 1899 carnivoran
 Macroscelidea - Amphilemuridae
Scenopagus priscus Marsh 1872 elephant shrew
Scenopagus edenensis McGrew et al. 1959 elephant shrew
Crypholestes sp.1 Novacek 1980 elephant shrew
 Trogontia - Esthonychidae
Trogosus sp. Leidy 1871 tillodont
 Chiroptera - Natalidae
cf. Ageina sp. Russell et al. 1973 funnel-eared bat
a bat
 Ungulata - Hyopsodontidae
Hyopsodus paulus Leidy 1870 condylarth
confirmed by Redline 1997
Hyopsodus minusculus3 Leidy 1873 condylarth
 Ungulata - 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
 Insectivora -
Aethomylos simplicidens Novacek 1976 insectivoran
 Insectivora - Apatemyidae
Apatemys cf. rodens Troxell 1923 insectivoran
Apatemys cf. bellus Marsh 1872 insectivoran
Apatemys cf. bellulus Marsh 1872 insectivoran
 Acreodi - Mesonychidae
Mesonychidae indet. Cope 1875 condylarth
 Hyaenodonta -
Limnocyon cf. verus Marsh 1872 eutherian
 Hyaenodonta - Hyaenodontidae
Proviverroides cf. piercei4 Bown 1982 eutherian
Sinopa rapax1 Leidy 1871 eutherian
Sinopa major1 Wortman 1902 eutherian
Tritemnodon cf. agilis4 Marsh 1872 eutherian
 Theriiformes - Peradectidae
Armintodelphys dawsoni Krishtalka and Stucky 1983 metatherian
Peradectes chesteri Gazin 1952 metatherian
 Theriiformes - Herpetotheriidae
"Copedelphys innominata" = Herpetotherium innominatum1, "Herpetotherium marsupium" = Peratherium marsupium1
"Copedelphys innominata" = Herpetotherium innominatum1 Simpson 1928 marsupial
"Herpetotherium marsupium" = Peratherium marsupium1 Troxell 1923 marsupial