Cimolestes is a genus of early eutherians with a full complement of teeth adapted for eating insects and other small animals. Paleontologists have disagreed on its relationship to other mammals, in part because quite different animals were assigned to the genus, making Cimolestes a grade taxon of animals with similar features rather than a genus of closely related ones. Fossils have been found in North America and Africa. Cimolestes first appeared during the Early Cretaceous of South Africa. According to some paleontologists, Cimolestes died out at the start of the Paleocene, while others report the genus from the early Eocene.
The Nacimiento Formation is a sedimentary rock formation found in the San Juan Basin of western New Mexico. It has an age of 61 to 65.7 million years, corresponding to the early and middle Paleocene. The formation has yielded an abundance of fossils from shortly after the Cretaceous-Paleogene extinction event that provide clues to the recovery and diversification of mammals following the extinction event.
The Ojo Alamo Formation is a geologic formation in New Mexico spanning the Mesozoic/Cenozoic boundary. Non-avian dinosaur fossils have controversially been identified in beds of this formation dating from after the Cretaceous–Paleogene extinction event, but these have been explained as either misidentification of the beds in question or as reworked fossils, fossils eroded from older beds and redeposited in the younger beds.
The Willwood Formation is a sedimentary sequence deposited during the late Paleocene to early Eocene, or Clarkforkian, Wasatchian and Bridgerian in the NALMA classification.
The Hannold Hill Formation is an Early Eocene (Wasatchian) geologic unit in the western United States. It preserves the fossilized remains of the ray Myliobatis and gar.
The Williamsburg Formation is a geologic formation in South Carolina consisting of sandy shale and clayey sand. It is a member of the Black Mingo Group and overlays the Rhems Formation. It preserves fossils, among others coprolites, dating back to the Paleogene period.
The Tatman Formation is a Wasatchian geologic formation in Wyoming. It preserves fossils dating back to the Ypresian stage of the Eocene period.
The Wasatch Formation (Tw) is an extensive highly fossiliferous geologic formation stretching across several basins in Idaho, Montana Wyoming, Utah and western Colorado. It preserves fossils dating back to the Early Eocene period. The formation defines the Wasatchian or Lostcabinian, a period of time used within the NALMA classification, but the formation ranges in age from the Clarkforkian to Bridgerian.
The Indian Meadows Formation is a Wasatchian geologic formation in Wyoming. It preserves fossils dating back to the Ypresian stage of the Eocene period.
The Pass Peak Formation is a Wasatchian geologic formation in Wyoming. It preserves fossils dating back to the Ypresian stage of the Eocene period.
The Galisteo Formation is a geologic formation in New Mexico. It contains fossils characteristic of the Bartonian stage of the Eocene epoch, Duchesnean in the NALMA classification.
The San Jose Formation is an Early Eocene geologic formation in the San Juan Basin of New Mexico and Colorado.
The Mint Canyon Formation (Tm) is a Miocene geologic formation in the Sierra Pelona Mountains of Los Angeles County, southern California. The formation preserves fossils dating back to the Middle to Late Miocene.
The Margaret Formation is a geologic formation of the Eureka Sound Group in the Sverdrup Basin in Northwest Territories and Nunavut, Canada. The unit belonging to the Eureka Sound Group which crops out at Ellesmere Island preserves fossils dating back to the Early Eocene period, or Wasatchian in the NALMA classification.
The Coldwater Beds are a geologic formation of the Okanagan Highlands in British Columbia, Canada. They preserve fossils dating back to the Ypresian stage of the Eocene period, or Wasatchian in the NALMA classification.
The Lignites de Soissonais is a geologic formation in the Var, Marne departments of France. It preserves fossils dating back to the Ypresian stage of the Eocene period.
The Argiles d'lignite du Soissonnais is a geologic formation in the Oise department of northern France. The formation has provided fossil mammals, reptiles and fish as well as arthropods in the amber of the formation. The Argiles d'lignite du Soissonnais dates back to the Ypresian stage of the Eocene period.
Azygonyx was a small tillodont mammal, likely the size of a cat to raccoon, that lived in North America during the Paleocene and Eocene in the early part of the Cenozoic Era. The only fossils that have been recovered are from the Willwood and Fort Union Formations in the Bighorn Basin of Wyoming, United States, and date to the Clarkforkian to Wasatchian, about 56 to 50 million years ago. Fifty-six collections that have been recovered thus far include the remains of Azygonyx. Azygonyx survived the Paleocene Eocene Thermal Maximum along with other mammals like Phenacodus and Ectocion, both of which were ground-dwelling mammals. Azygonyx probably was a generalist terrestrial mammal that may have roamed around the ground, but was also capable of climbing trees.
The Silveirinha Formation is an Early Eocene geologic formation of the Mondego Basin in the Região Centro of central-western Portugal. The sandstones, siltstones and conglomerates were deposited in an alluvial environment.
The Alai Beds is an Early Eocene geologic formation in the Osh Region of southwestern Kyrgyzstan. The formation has provided many fossils of mammals, lizards, turtles and snakes.
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