Paleocene genus extinctions

Purgatorius is an extinct genus of eutherian mammal from the early Paleocene epoch of western North America. It is typically believed to be the earliest example of a primate or protoprimate (a primatomorph precursor to the Plesiadapiformes), dating to nearly as old as 66 million years ago.

Sinonyx ("Chinese claw") is a genus of extinct, superficially wolf-like mesonychid mammals from the late Paleocene of China (about 56 million years ago). It is within the family Mesonychidae, and cladistic analysis of a skull of Sinonyx jiashanensis identifies its closest relative as Ankalagon. S. jiashanensis was discovered in Anhui province, China (, paleocoordinates ), in the Tuijinshan formation.

Arctocyon (from Ancient Greek ἄρκτος (árktos), meaning "bear", and κύων (kúon), meaning "dog", and thus, "bear-dog") is an extinct genus of large placental mammals, part of the possibly polyphyletic family Arctocyonidae. The type species is A. primaevus, though up to five other species may be known. Fossils of Arctocyon have been found in Europe and North America. Arctocyon was originally named as a subgenus of the bear-dog Amphicyon, though was subsequently found to belong to a genus and family of its own. The relationship between arctocyonids and other placentals is unclear, with early class

Psittacotherium ("parrot beast") is an extinct genus of taeniodonts from extinct tribe Psittacotheriini within subfamily Stylinodontinae and family Stylinodontidae, that lived in North America from early to late Paleocene. With a weight between and , and length of , it had similar size of a large dog.

Taeniolabis ("banded incisor") is a genus of extinct multituberculate mammal from the Paleocene of North America.

Prodinoceras, from Ancient Greek πρό (pró), meaning "before", δεινός (deinós), meaning "terrible", and κέρας (kéras), meaning "horn", is the earliest known dinocerate genus, which lived in the late Paleocene of Mongolia.

Echinocorys is an extinct genus of echinoids that lived from the Late Cretaceous to the Paleocene. The genus belongs to the Holasteridae family. Its remains have been found in Asia, Europe, Australia (Oceania) and North America.

Mesodma is an extinct genus of mammal, a member of the extinct order Multituberculata within the suborder Cimolodonta, family Neoplagiaulacidae. It lived during the upper Cretaceous and Paleocene Periods of what is now North America. The earliest definitive record is from the late Santonian stage strata of the Straight Cliffs Formation. A single premolar tooth from the lower Cenomanian stage strata of the Cedar Mountain Formation has been tentatively assigned to this genus based on its similarity, but its describers noted that it is unlikely that Mesodma lived during that time.

Bisonalveus ("animal from Bison Basin") is an extinct genus of placental mammals from family Pentacodontidae, that lived during the middle to late Paleocene. Bisonalveus fossils have been discovered in the upper Great Plains region of North America, including sites in modern-day Wyoming, North Dakota, Montana, and Alberta.

Hyposaurus is a genus of extinct marine dyrosaurid crocodyliform. Fossils have been found in Paleocene aged rocks of the Iullemmeden Basin in West Africa, Campanian–Maastrichtian (Late Cretaceous) Shendi Formation of Sudan and Maastrichtian (Late Cretaceous) through Danian (Early Paleocene) strata in New Jersey, Alabama and South Carolina. With an Indeterminate species from the Mid to Late Palaeocene Teberemt Formation of Mali. Isolated teeth comparable to Hyposaurus have also been found in Thanetian (Late Paleocene) strata of Virginia. It was related to Dyrosaurus. The priority of the species

Eoconodon is an extinct genus of triisodontid mesonychian that existed during the early Paleocene of North America. Characteristics of the genus include massive jaws, blunt builds, and strong canine teeth. thumb|left|E. coryphaeus jaw Eoconodon is considered to be a giant for mammals during the Early Paleocene, with E. coryphaeus weighing up to .

thumb|right|225px|Diagram of Trigonia costata James Parkinson, showing main morphological features of the shell exterior;a) [[Anterior; p) Posterior; d) Dorsal; v) Ventral; F) Flank; A) Area; c) Costae; mc) Marginal CarinaTrigonia costata ranges from the Lower Jurassic (Toarcian) to Middle Jurassic (Callovian).]] thumb|350x350px|Trigonia sp. from the Jurassic of the Canjuers plateau, Var, France. Max Rouger Collection. Trigonia is an extinct genus of saltwater clams, fossil marine bivalve mollusk in the family Trigoniidae. The fossil range of the genus spans the Paleozoic, Mesozoic and Paleoce

Prionessus is a genus of extinct mammal from the Paleocene of what is now Central Asia. It was a member of the extinct order Multituberculata within the suborder Cimolodonta and superfamily Taeniolabidoidea. The genus was named by William Diller Matthew and Walter Granger in 1925, and is based on a single species P.lucifer.

Pentacodontidae ("teeth with five points") is an extinct family of placental mammals from extinct order Pantolesta, that lived in North America and Europe from the early to late Paleocene.

Wortmania ("Wotman's animal") is an extinct genus of taeniodonts from extinct subfamily Wortmaniinae within extinct family Stylinodontidae, that lived in North America during the early Paleocene.

Lambdopsalis is an extinct multituberculate mammal from the Late Paleocene of China and Mongolia. It is placed within the suborder Cimolodonta and is a member of the superfamily Taeniolabidoidea. Fossil remains have been found in the Late Paleocene Nomogen and Khashat Formations in Nao-mugen and Bayn Ulan of China and Mongolia, dated to 59-55 million years ago from the Thanetian age. Lambdopsalis bulla is the type species of this genus. The genus and species were named by Chow and Tao Qi in 1978.

Kimbetohia is a genus of mammal belonging to the extinct order Multituberculata. It lived from the Upper Cretaceous to the Paleocene period in the United States.

Hainina is an extinct mammal genus from the latest Cretaceous to the Paleocene of Europe.

Temnocidaris is an extinct genus of echinoids that lived from the Late Cretaceous to the Paleocene. Its remains have been found in Europe and North America.

Habrosaurus, meaning "graceful lizard", is an extinct genus of prehistoric salamanders, and the oldest and largest known member of the family Sirenidae. Two species are known, H. prodilatus from the middle Campanian Dinosaur Park Formation of Alberta, and H. dilatus from the late Maastrichtian and Paleocene of western North America. It is relatively common in the Lance Formation of Wyoming, and less common in the Hell Creek Formation of Montana. left|thumb|Artists reconstruction of Habrosaurus dilatus swimming by a cypress tree

Acheronodon is a genus of herbivorous arboreal mammal which belongs to the family Microcosmodontidae and which was endemic to North America during the Early Paleocene subepoch (66—56.8 mya) and in existence for approximately .

Eucosmodon is a genus of extinct mammal from the Paleocene of North America. It is a member of the extinct order of Multituberculata within the suborder of Cimolodonta, and the family Eucosmodontidae. This genus has partly also been known as Neoplagiaulax. All known fossils of this small mammal are restricted to teeth.

Pentacosmodon is a mammal genus from the Paleocene of North America, so it lived somewhat after the "age of the dinosaurs". It was a member of the extinct order Multituberculata. It's within the suborder Cimolodonta and family Microcosmodontidae.

Sphenopsalis is a genus of extinct mammal from the Paleocene of what is now Central Asia. It was a member of the extinct order Multituberculata, and lies within the suborder Cimolodonta and the superfamily Taeniolabidoidea. The genus was named by William Diller Matthew, W. Granger and George Gaylord Simpson in 1928.