The Monroe Creek Formation is a geologic formation in South Dakota. It preserves fossils dating back to the Paleogene period.

Fossil content

Mammals Carnivorans Carnivorans reported from the Monroe Creek Formation Genus Species Presence Material Notes ImagesEnhydrocyonE. crassidensShannon County, South Dakota.Crushed skull (AMNH 12886) & other skull elements.A hesperocyonine dog.E. pahinsintewakpaMultiple specimens.A hesperocyonine dog.LeptocyonL. delicatusPorcupine Creek, South Dakota.Left partial ramus (ACM 31102).A canine dog, may instead be from the Harrison Formation.MammacyonM. obtusidensWounded Knee Area.Skull & partial skeleton (ACM 34-41).A bear-dog.NeocynodesmusN. delicatusPorcupine Creek, Wounded Knee Area.Left mandible (ACM 31102).Junior synonym of Leptocyon.NimravusN. sectatorWounded Knee Area.Left ramus (AMNH 12882).Possibly instead from the Harrison Formation.NothocyonN. geismarianusWounded Knee Area.Fragmentary ramus (AMNH 12872).An arctoid formerly thought to be a canid.N. near latidensWounded Knee Area.Jaw fragment (AMNH 12873).Reassigned to Phlaocyon.PromartesP. gemmarosaeWounded Knee Area.Nearly-complete skeleton (ACM 31-33).A mustelid.

Eulipotyphlans Eulipotyphlans reported from the Monroe Creek Formation Genus Species Presence Material Notes ImagesProscalopsP. sp. indeterminateWounded Knee Area.Isolated molar (SDSM 5899).A proscalopid.

Rodents Rodents reported from the Monroe Creek Formation Genus Species Presence Material Notes Images AllomysA. harkseni Wounded Knee Area.Molars. An aplodontid. CapatankaC. brachycepsWounded Knee Area.Skull (AMNH 12902).A castorid, possibly instead from the Harrison Formation.MeniscomysM. sp. indeterminateWounded Knee Area.Isolated tooth (SDSM 59157).An aplodontid.PalaeocastorP. simplicidensWounded Knee Area.Partial cranium (AMNH 12900).A castorid.PleurolicusP. dakotensisWounded Knee Area.Left ramus (AMNH 12893).A gopher.PromylagaulusP. cf. riggsiWounded Knee Area.Isolated molar.A mylagaulid.

Ungulates Ungulates reported from the Monroe Creek Formation Genus Species Presence Material Notes ImagesNanotragulusN. ordinatusWounded Knee Area.Mandibles.May instead be from the Harrison Formation. ParahippusP. pristinus Wounded Knee Area.Hind feet (AMNH 12922). May instead be from the Harrison Formation.

Reptiles Squamates Squamates reported from the Monroe Creek Formation Genus Species Presence Material Notes ImagesPeltosaurusP. granulosusSharps Corner, South Dakota.Multiple specimens.A glyptosaurine also known from the Sharps Formation.

See also

List of fossiliferous stratigraphic units in South Dakota Paleontology in South Dakota

References