# Pisco Formation

The Pisco Formation is a geologic formation located in Peru, on the southern coastal desert of Ica and Arequipa. The approximately 640 metres (2,100 ft) thick formation was deposited in the Pisco Basin, spanning an age from the Late Miocene up to the Early Pliocene, roughly from 9.6 to 4.5 Ma. The tuffaceous sandstones, diatomaceous siltstones, conglomerates and dolomites were deposited in a lagoonal to near-shore environment, in bays similar to other Pacific South American formations as the Bahía Inglesa and Coquimbo Formations of Chile.
Several specialists consider the Pisco Formation one of the most important Lagerstätten, based on the large amount of exceptionally preserved marine fossils, including sharks (most notably megalodon), penguins, whales, dolphins, birds, marine crocodiles and aquatic giant sloths.
Famous fossils found in these layers include the giant raptorial sperm whale Livyatan, the aquatic sloth Thalassocnus, the sperm whale Acrophyseter, and the walrus-like dolphin Odobenocetops.

## Description

The Pisco Formation of the Pisco Basin consists of tuffaceous sandstones, diatomaceous yellow to gray siltstones and a basal conglomerate. The formation is deposited from Pisco in the north to Yauca in the south. The northern portion is known as the Ocucaje Area and the southern part as the Sacaco Area. The total thickness of the formation is estimated at 640 metres (2,100 ft). The formation unconformably overlies the Chilcatay and Caballas Formations.

## Paleobiota of the Pisco Formation

The Pisco Formation has provided a rich resource of marine fauna, including marine mammals like cetaceans and seals, large fishes, reptiles, and penguins. It is also one of the richest sites in the world for fossil cetaceans, with close to 500 examples being found in the formation.
The oldest fossils of the aquatic sloth Thalassocnus (T. antiquus) come from the Aguada de Lomas horizon of the Pisco Formation and were dated at roughly 7 Ma. The youngest specimen (T. carolomartini) was found in the Sacaco horizon and dated to approximately 3 Ma. Thalassocnus was preyed upon by the probable apex predators of the environment, Livyatan and megalodon. The youngest strata belonging to the formation have been dated at 2 Ma, corresponding to the Early Pleistocene (Uquian). Fossils of the Humboldt penguin were found in these deposits at the Yauca locality.

### Birds

| Taxa | Species | Description |
| Spheniscus | S. humbodti | Humboldt penguin |
| Spheniscus | S. megarhampus | Banded penguin |
| Spheniscus | S. muizoni | The oldest banded penguin |
| Spheniscus | S. urbinai | A larger banded penguin than S. muizoni |
| Ramphastosula | R. aguierrei | |
| Ramphastosula | R. ramirezi | |
| Sula | S. brandi | |
| Sula | S. magna | |
| Sula | S. sulita | |
| Morus | M. peruvianus | |
| Perugyps | P. diazi | |
| Ciconiidae indet. | Gen. et sp. indet. | |
| Fulmarus | Fulmarus sp. | |
| Pelagornis | Pelagornis sp. | |
| Pelecanus | Pelecanus sp. | |
| Phalacrocorax | P. aff. bougainvillii | |
| Phalacrocorax | cf. Phalacrocorax sp. | |

### Fish
#### Bony fish

| Taxa | Species | Description |
| Alosinae | A. indet | A type of herring |
| Centropomidae | C. aff. Psamoperca | A snook fish |
| Triglidae | T. indent | A type of sea robin |
| Xiphiidae | X. ident | A sword fish |
| Sardinops | S. sp. | A sardine |

#### Rays

| Taxa | Species | Description | Images | Notes |
| Myliobatis | Indeterminate | A species of eagle ray | | |

#### Sharks

| Taxa | Species | Description |
| Carcharias | C. taurus | The sand tiger shark |
| Carcharhinus | C. sp. indent | A requiem shark |
| Carcharodon | C. carcharias | The great white shark |
| Carcharodon | C. hubbelli | The great white shark |
| Cosmopolitodus | C. hastalis | The broad-toothed mako |
| Hexanchus | H. gigas | A cow shark |
| Isurus | I. oxyrhincus | The shortfin mako |
| Otodus | O. chubutensis | |
| Otodus | O. megalodon | The largest of the megatoothed sharks (and of all fishes) |

### Mammals
#### Cetaceans

| Taxa | Species | Description |
| Acrophyseter | A. deinodon | A small raptorial physeteroid |
| Acrophyseter | A. robustus | A small raptorial physeteroid |
| Atocetus | A. iquensis | A small toothed whale |
| Australithax | A. intermedia | A long-snouted porpoise |
| Balaenoptera | B. siberi | A baleen cetacean |
| Belonodelphis | B. peruanus | A long delphinid |
| Brachydelphis | B. jahuayensis | An early delphinid |
| Brachydelphis | B. mazeasi | An early delphinid |
| Brujadelphis | B. ankylorostris | A river delphinid |
| Hemisyntrachelus | H. oligodon | An early form of orca |
| Incakujira | I. anillodefuego | A small baleen cetacean |
| Incakujira | I. fordycei | A small baleen cetacean |
| Kogia | K. danomurai | A basal member of the Kogia genus. Small physeteroid |
| Koristocetus | K. pescei | A small sperm whale |
| Livyatan | L. melvillei | An 18-meter long raptorial physeteroid with 36 centimetres (1.18 ft) teeth |
| Lomacetus | L. ginsburgi | A cetacean |
| Mamaziphius | M. reyesi | An early beaked whale. |
| Miocaperea | M. pulchra | A cetothere whale |
| Ninoziphius | N. platyrostris | A giant beaked whale |
| Odobenocetops | O. leptodon | A cetacean with dual tusks |
| Odobenocetops | O. peruvianus | A cetacean with dual tusks |
| Piscobalaena | P. nana | A small baleen whale |
| Piscocetus | P. sacaco | An extinct cetacean |
| Piscolithax | P. aenigmaticus | A porpoise |
| Pliopontos | P. littoralis | An early delphinid |
| Scaphokogia | S. cochlearis | An extinct pygmy sperm whale |

#### Pinnipeds
##### Seals

| Taxa | Species | Description |
| Acrophoca | A. longirostirus | A large pinniped thought to be the ancestor of the leopard seal |
| Australophoca | A. changorum | A phocidae seal. |
| Hadrokirus | H. martini | A species of true seal |
| Hydrarctos | H. lomasiensis | An Otariidae seal. |
| Magophoca | M. brevirostris | A monachinae seal. |
| Piscophoca | P. pacifica | A phocidae seal |

#### Xenarthrans
##### Sloths

| Taxa | Species | Description | Notes |
| Thalassocnus | T. antiquus | a semi-aquatic marine sloth | [5][18] [20][28] |
| Thalassocnus | T. carolomartini | a semi-aquatic marine sloth | [5][18] [20][28] |
| Thalassocnus | T. littoralis | a semi-aquatic marine sloth | [5][18] [20][28] |
| Thalassocnus | T. natans | a semi-aquatic marine sloth | [5][18] [20][28] |

### Mollusks
#### Bivalves

| Taxa | Species | Description | Images | Notes |
| Dosinia | Indeterminate | | | |

#### Polychaetes

| Taxa | Species | Description | Images | Notes |
| Diplochaetetes | D. mexicanus | | | |

#### Gastropods

| Taxa | Species |
| Acanthina | A. obesa |
| Acanthina | A. triangularis |
| Concholepas | C. kieneri |
| Herminespina | Indeterminate |

### Reptiles

| Taxa | Species | Description |
| Sacacosuchus | S. cordovai | A gavialid crocodylian |
| Piscogavialis | P. jugaliperforatus | A gryposuchine gavialid crocodylian |
| Pacifichelys | P. urbinai | A sea turtle |
| Chelonia | Indeterminate | |
| Eusuchia | Indeterminate | |

## Correlations
### Laventan

Laventan correlations in South America :
| Formation | Honda | Honda | Aisol | Cura-Mallín | Pisco | Ipururo | Pebas | Capadare | Urumaco | Inés | Paraná | Map |
| Basin | VSM | Honda | San Rafael | Caldera | Pisco | Ucayali | Amazon | Falcón | Falcón | Venezuela | Paraná | Pisco Formation (South America) |
| Country | Colombia | Bolivia | Argentina | Chile | Peru | Peru | Peru | Venezuela | Venezuela | Venezuela | Argentina | Pisco Formation (South America) |
| Boreostemma | | | | | | | | | | | | Pisco Formation (South America) |
| Hapalops | | | | | | | | | | | | Pisco Formation (South America) |
| Miocochilius | | | | | | | | | | | | Pisco Formation (South America) |
| Theosodon | | | | | | | | | | | | Pisco Formation (South America) |
| Xenastrapotherium | | | | | | | | | | | | Pisco Formation (South America) |
| Mylodontidae | | | | | | | | | | | | Pisco Formation (South America) |
| Sparassodonta | | | | | | | | | | | | Pisco Formation (South America) |
| Primates | | | | | | | | | | | | Pisco Formation (South America) |
| Rodents | | | | | | | | | | | | Pisco Formation (South America) |
| Birds | | | | | | | | | | | | Pisco Formation (South America) |
| Terror birds | | | | | | | | | | | | Pisco Formation (South America) |
| Reptiles | | | | | | | | | | | | Pisco Formation (South America) |
| megalodon | | | | | | | | | | | | Pisco Formation (South America) |
| Flora | | | | | | | | | | | | Pisco Formation (South America) |
| Insects | | | | | | | | | | | | Pisco Formation (South America) |
| Environments | Fluvial | Fluvial | Fluvial | Fluvio-deltaic | Fluvio-deltaic | Fluvio-lacustrine | Fluvio-lacustrine | Fluvio-deltaic | Fluvio-deltaic | Fluvio-deltaic | Fluvial | Laventan volcanoclastics Laventan fauna Laventan flora |
| Volcanic | Yes | Yes | Yes | | | | | | | | | | Laventan volcanoclastics Laventan fauna Laventan flora |