Cretaceous Chile

Aristonectes (meaning "best swimmer") is an extinct genus of large elasmosaurid plesiosaurs that lived during the Maastrichtian stage of the Late Cretaceous. Two species are known, A. parvidens and A. quiriquinensis, whose fossil remains were discovered in what are now Patagonia and Antarctica. Throughout the 20th century, Aristonectes was a difficult animal for scientists to analyze due to poor fossil preparation, its relationships to other genera were uncertain. After subsequent revisions and discoveries carried out from the beginning of the 21st century, Aristonectes is now recognised as th

Pachydiscus is an extinct genus of ammonite from the Late Cretaceous and Early Paleocene with a worldwide distribution, and type for the desmoceratacean family Pachydiscidae. The genus' type species is P. neubergicus. Altogether some 28 species have been described.

thumb|250px|A rare heteromorph ammonite fossil from the south of France. The species is Crioceratites nolani and the spines have been partially restored to show how it might have appeared in life

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

Cymatoceras is a wide-ranging extinct genus from the nautilitacean cephalopod family, Cymatoceratidae. They lived from the Late Jurassic to Late Oligocene, roughly from 155 to 23 Ma.

Magallanodon is a genus of large mammal from the extinct group Gondwanatheria. It contains a single species, Magallanodon baikashkenke. The species is the first Mesozoic mammal known from Chile, and is Late Cretaceous in age. It is known from individual teeth found in a quarry in the Río de Las Chinas Valley and La Anita Farm located in the Magallanes Basin in Patagonia. The fossils come from the Dorotea Formation and Chorrillo Formation, which is Late Campanian to Early Maastrichtian in age. It was more recently estimated to weigh ~10.34 kg.

Aspidoceras is an extinct ammonoid cephalopod genus belonging to the family Aspidoceratidae.

Orretherium (meaning "Five teeth beast"; in part from the Aonikenk language) is a genus of mesungulatid mammal that lived in South America (Chile) during the Late Cretaceous period in what is now the Dorotea Formation. It is estimated to have weighed ~1.3kg.

Hoploscaphites is an extinct ammonite genus from the Upper Cretaceous and the Lower Paleocene, included in the family Scaphitidae.

Acanthodiscus is an extinct ammonoid cephalopod genus from the order Ammonitida and included in the persphinctacean family Berriasellidae. The type species, named by Bruguière, 1792, is Acanthodiscus radiatus.

Olcostephanus is an extinct ammonoid cephalopod genus belonging to the family Olcostephanidae. These fast-moving nektonic carnivores lived during the Cretaceous, from the upper Valanginian to the lower Hauterivian age.