Washakie A (Eocene of the United States)

Also known as LaClede Meadows

Where: Sweetwater County, Wyoming (41.7° N, 109.0° W: paleocoordinates 45.6° N, 95.1° W)

• coordinate based on political unit

When: Br3 mammal zone, Washakie Formation, Bridgerian (50.3 - 46.2 Ma)

• McCarroll et al. 1996 correlate older collections listed as "Washakie A" with both the Kinney Rim and lowest unit of the Adobe Town Member. Both members are considered late Bridgerian (Br3) in age.

Environment/lithology: terrestrial; lithology not reported

Size class: macrofossils

Primary reference: S. Tomiya, S. P. Zack, M. Spaulding and J. J. Flynn. 2021. Carnivorous mammals from the middle Eocene Washakie Formation, Wyoming, USA, and their diversity trajectory in a post-warming world. Journal of Paleontology Memoir 95(82):1-115 [P. Holroyd/P. Holroyd]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 16647: authorized by John Alroy, entered by John Alroy on 26.07.1994, edited by Roger Benson

Creative Commons license: CC BY (attribution)

Taxonomic list

• this unit spans beds 569 to 620 of Roehler; most of this interval is reversed, but there are two normal excursions of unclear significance; it is best treated as a reversed chron immediately preceding the normal chron seen in the overlying unit
Turnbull 1972 distinguished "upper" and "lower" Washakie A faunas but the upper fauna is duplicated almost entirely by the lower fauna and the two are merged by McCarroll et al.; list is still incomplete and certain older i.d.s therefore may be valid
Mammalia
 Dinocerata - Uintatheriidae
Uintatherium anceps4 Marsh 1871 uintathere
listed as "Dinoceras cuneum" and "Tinoceras affine" by Turnbull 1972
 Tribosphenida - Herpetotheriidae
Herpetotherium cf. knighti1 McGrew et al. 1959 marsupial
 Acreodi - Mesonychidae
Harpagolestes sp.4 Wortman 1901 condylarth
probably "Synoplotherium sp." of Turnbull 1972
 Ferae -
"Miacis washakius" = Neovulpavus washakius4, "Miacis cf. sylvestris" = Harpalodon sylvestris4, "Miacis medius" = Lycarion medius4
"Miacis washakius" = Neovulpavus washakius4 Wortman 1901 placental
"Miacis cf. sylvestris" = Harpalodon sylvestris4 Marsh 1872 placental
"Miacis medius" = Lycarion medius4 Matthew 1909 placental
 Ferae - Viverravidae
Viverravus sp.4 Marsh 1872 placental
 Creodonta - Hyaenodontidae
Sinopa sp.4 Leidy 1871 creodont
listed as "S. rapax" by Turnbull
 Creodonta - Oxyaenidae
Patriofelis ferox2 Marsh 1872 creodont
 Perissodactyla - Hyrachyidae
Hyrachyus eximius4 Leidy 1871 odd-toed ungulate
Hyrachyus modestus4 Leidy 1870 odd-toed ungulate
 Perissodactyla -
Isectolophus latidens4 Osborn et al. 1878 odd-toed ungulate
 Perissodactyla - Equidae
Orohippus sp.4 Marsh 1872 horse
 Perissodactyla - Brontotheriidae
Mesatirhinus sp.4 Osborn 1908 brontothere
listed as "M. megarhinus" by Turnbull
Telmatherium sp.4 Marsh 1872 brontothere
based on discussion of Mader 1989, I believe this includes the type of "Manteoceras washakiensis" Osborn 1908 from "Base of Haystack Mountain... summit of the Lower Washakie (A)" (said by Roehler 1973 to be upper Washakie A
Palaeosyops sp.4 Leidy 1870 brontothere
this is the AMNH "P. copei" specimen of Osborn 1929 from Washakie A; may include "Titanotheriidae indet." of Turnbull 1972
 Artiodactyla - Homacodontidae
Homacodon vagans4 Marsh 1872 even-toed ungulate
 Tribosphenida - Pantolestoidae
Pantolestidae indet.1 Cope 1884 placental
Pantolestes cf. longicaudus4 Cope 1872 placental
Pantolestes cf. natans4 Matthew 1909 placental
 Primates - Omomyidae
Hemiacodon gracilis4 Marsh 1872 tarsier
Omomys carteri4 Leidy 1869 tarsier
 Primates - Microsyopidae
Microsyops annectens4 Marsh 1872 primate
 Primates - Notharctidae
Notharctus robustior4 Leidy 1872 primate
 Rodentia - Sciuravidae
Sciuravus sp.4 Marsh 1871 rodent
Sciuravus nitidus4 Marsh 1871 rodent
 Rodentia - Muridae
Mysops parvus4 Marsh 1872 mouse
 Rodentia - Ischyromyidae
Thisbemys sp.4 Wood 1959 rodent
Paramys sp.4 Leidy 1871 rodent
listed as "P. delicatus" by Turnbull
Leptotomus parvus1 Wood 1959 rodent
 Condylarthra - Hyopsodontidae
Hyopsodus paulus4 Leidy 1870 condylarth
 Cimolesta - Apatemyidae
cf. Apatemys bellus4 Marsh 1872 eutherian
 Taeniodonta - Stylinodontidae
"Stylinodon mirus" = Stylinodon mirus4, "Stylinodon inexplicatus n. sp." = Stylinodon mirus4
"Stylinodon mirus" = Stylinodon mirus4 Marsh 1874 taeniodont
"Stylinodon inexplicatus n. sp." = Stylinodon mirus4 Marsh 1874 taeniodont
and only specimen according to Schoch and Lucas 1981b
Reptilia
 Testudinata - Baenidae
Baena arenosa3 Leidy 1870 turtle
AMNH 1115 (Hay, 1908, figs. 49-5 1), shell, portion of pelvis.