Fossils of Costa Rica

A nummulite is a large lenticular fossil, characterised by its numerous coils, subdivided by septa into chambers. They are the shells of the fossil and present-day marine protozoan Nummulites, a type of foraminiferan. Nummulites commonly vary in diameter from and are common in Eocene to Miocene marine rocks, particularly around southwest Asia and the Mediterranean in the area that once constituted the Tethys Ocean, such as Eocene limestones from Egypt or from Pakistan. Fossils up to six inches wide are found in the Middle Eocene rocks of Turkey. They are valuable as index fossils.

Eremotherium (from Greek for "steppe" or "desert" "beast": ἔρημος "steppe or desert" and θηρίον "beast") is an extinct genus of giant ground sloth in the family Megatheriidae. Eremotherium lived in southern North America, Central America, and northern South America. It was one of the largest sloths, with a body size comparable to elephants, weighing around and measuring about long, slightly larger than its close relative Megatherium.

Cuvieronius is an extinct New World genus of gomphothere which ranged from southern North America to northwestern South America during the Pleistocene epoch. Reaching a shoulder height of and a body mass of , it was comparable in size to an Asian elephant. Cuvieronius inhabited subtropical and tropical latitudes in environments ranging from grasslands to tropical rainforest. Among the last gomphotheres along with the South American Notiomastodon, it became extinct as part of the end Pleistocene-extinction event, approximately 12-11,000 years ago, along with most other large mammals in the Amer

Holmesina is an extinct genus of pampathere, a group of armadillo-like xenarthrans that were distantly related to extant armadillos. Like armadillos, and unlike the other extinct branch of megafaunal cingulates the glyptodonts, the shell was made up of flexible plates which allowed the animal to move more easily. thumb|left|Holmesina occidentalis thumb|left|Life reconstruction of Holmesina floridanus and size comparation Holmesina individuals were much larger than any modern armadillo: They could reach a length of , and a weight of , while the modern giant armadillo does not attain more than

Glyptotherium (from Ancient Greek for 'grooved or carved beast') is a genus of glyptodont (an extinct group of large, herbivorous armadillos) in the family Chlamyphoridae that lived from the Early Pliocene, about 3.9 million years ago, to the Late Pleistocene, around 15,000 years ago. It was widely distributed, living in the United States, Mexico, Guatemala, Costa Rica, Honduras, El Salvador, Panama, Venezuela, Colombia, and Brazil. Fossils that had been found in the Pliocene Blancan Beds in Llano Estacado, Texas were named Glyptotherium texanum by American paleontologist Henry Fairfield Osbor

Dinohippus (from Ancient Greek δεινός (deinós), meaning "terrible", and ἵππος (híppos), meaning "horse") is an extinct equid which was endemic to North America from the late Hemphillian stage of the Miocene through the Zanclean stage of the Pliocene (10.3—3.6 mya) and in existence for approximately . Fossils are widespread throughout North America, being found at more than 30 sites from Florida to Alberta and from Mexico all the way down to Panama (Alajuela Formation). The majority of fossils of Dinohippus have been unearthed in the Western United States in Nevada, New Mexico, Utah, and Califo

Mixotoxodon ("mixture Toxodon") is an extinct genus of notoungulate of the family Toxodontidae inhabiting South America, Central America and parts of southern North America during the Pleistocene epoch, from 1,800,000–12,000 years ago.

Pliometanastes is an extinct genus of ground sloths of the family Megalonychidae endemic to North America during the Late Miocene epoch through very early Pliocene epoch (Hemphillian in the NALMA classification). Its fossils have been found in Costa Rica and across the southern United States from California to Florida.