Name: Leptictis dakotensis (skull)
Age: oligocene, brule formation
Origin: shannon county, South Dakota, USA
Size: 5.5 cm rareLeptictis is an extinct genus of leptictid non-placental eutherian mammal known from the Late Eocene to Early Oligocene of North America.The type spec..
Name: Sinclairella dakotensis (skull and vertebra)
Age: oligocene, brule formation
Origin: shannon county, South Dakota, USA
Size: 5.1 cm (skull)rare..