# Friasian

The Friasian age is a period of geologic time (16.3–15.5 Ma) within the Early Miocene epoch of the Neogene, used more specifically within the SALMA classification of South America. It follows the Santacrucian and precedes the Colloncuran age.

## Etymology

The age is named after the Río Frías Formation in the Aysén Basin, Patagonia, Chile.

## Formations

| Formation bold is type | Country | Basin |
| Río Frías Formation | Chile | Aysén Basin |
| Castilletes Formation | Colombia | Cocinetas Basin |
| Cerdas Beds | Bolivia | Altiplano Basin |
| Chilcatay Formation | Peru | Pisco Basin |
| Cura-Mallín Group | Chile | Cura-Mallín Basin |
| Gran Bajo del Gualicho Formation | Argentina | Colorado Basin |
| Parángula Formation | Venezuela | Barinas-Apure Basin |
| Pebas Formation | Brazil Colombia Ecuador Peru | Amazon Basin |
| Río Foyel Formation | Argentina | Patagonian Andes |
| Río Yuca Formation | Venezuela | Barinas-Apure Basin |

## Fossils

| Group | Fossils | Formation | Notes |
| Mammals | Abderites aisenense, A. meridionalis, Alloiomys friasensis, Astrapotherium hesperinum, Borhyaena tuberata, Cladosictis patagonica, Megathericulus friasensis, Microbiotherium tehuelchum, Parabderites bicrispatus, Palaeothentes intermedius, P. lemoinei, P. minutus, Pichipilus halleuxi, Pitheculites rothi, Prothylacinus patagonicus, Prototrigodon rothi, Sipalocyon gracilis, Adinotherium sp., Homalodotherium sp., Neonematherium sp., Nesodon sp., Pachyrukhos sp., Phoenixauchenia sp., ?Propalaehoplophorus sp., Protypotherium sp., Prozaedyus sp., Theosodon sp., Trachytypotherium sp., Platyrrhini indet. | Río Frías | [16] [17][18] |
| Mammals | Lycopsis padillai, ?Hyperleptus sp., Astrapotheriidae, Odontoceti, Mysticeti, Glyptodontidae, Pampatheriidae, Macraucheniidae, Proterotheriidae, Leontinidae, Toxodontidae, Interatheriidae, Megatheriidae, Dinomyidae, Sirenia, Sparassodonta | Castilletes | [19][20] [21] |
| Mammals | Hegetotherium cerdasensis, Juchuysillu arenalesensis, Llullataruca cf. shockeyi, Microtypotherium cf. choquecotense, Protypotherium cf. attenuatum, "Plesiotypotherium" minus, Palyeidodon obtusum, Mcdonaldocnus bondesioi, Borhyaenoidea indet., Euphractini indet., Lagostominae indet., Macraucheniidae indet., Megatheriinae indet., Mesotheriinae indet., Peltephilidae indet., Uruguaytheriinae indet. | Cerdas | |
| Mammals | Adinotherium sp., Peltephilidae indet. | Río Yuca | |
| Reptiles | Chelus colombiana, Chelonoidis sp., cf. Crocodylus sp., cf. Mourasuchus sp., cf. Purussaurus sp., Alligatoridae indet., Boidae indet., Eusuchia indet., Gavialoidea indet., Podocnemididae indet. | Castilletes | [21] [25][26] |
| Reptiles | Barinasuchus arveloi | Parángula | |
| Reptiles | Purussaurus sp. | Río Yuca | |
| Birds | Aves indet. | Castilletes | |
| Birds | Palaeospheniscus bergi, Spheniscidae indet. | Río Foyel | |
| Fish | Megalodon, Characidae, Serrasalmidae, Sciaenidae, Sparidae, Sphyraenidae, Ariidae, Callichthyidae, Doradidae, Pimelodidae, Carcharhinidae, Hemigaleidae, Sphyrnidae, Lamnidae, Otodontidae, Dasyatidae, Myliobatidae, Rhinopteridae, Ginglymostomatidae, Pristiophoridae, Pristidae, Rhynchobatidae, Rhynobatidae, Lepidosirenidae | Castilletes | |
| Fish | Carcharodon hastalis | Río Foyel | |
| Fish | Phractocephalus sp., Platysilurus sp. | Río Yuca | |