''Piscogavialis'' is an

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

monospecific In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispe ...

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of gryposuchine

gavialid Gavialidae is a family of large semiaquatic crocodilians with elongated, narrow snouts. Gavialidae consists of two living species, the gharial (''Gavialis gangeticus'') and the false gharial (''Tomistoma schlegelii''), both occurring in Asia. Man ...

crocodylia Crocodilia () is an Order (biology), order of semiaquatic, predatory reptiles that are known as crocodilians. They first appeared during the Late Cretaceous and are the closest living relatives of birds. Crocodilians are a type of crocodylomorp ...

n. The only species yet known is ''P. jugaliperforatus''. Fossils of ''Piscogavialis'' have been found from the Mio-

Pliocene The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58Pisco Formation The Pisco Formation is a geologic formation located in Peru, on the southern coastal desert of Ica, Peru, Ica and Arequipa. The approximately thick formation was deposited in the Pisco Basin, spanning an age from the Miocene, Late Miocene up to t ...

of the Sacaco Basin in southern

Peru Peru, officially the Republic of Peru, is a country in western South America. It is bordered in the north by Ecuador and Colombia, in the east by Brazil, in the southeast by Bolivia, in the south by Chile, and in the south and west by the Pac ...

1998 1998 was designated as the ''International Year of the Ocean''. Events January * January 6 – The ''Lunar Prospector'' spacecraft is launched into orbit around the Moon, and later finds evidence for Lunar water, frozen water, in soil i ...

,''Piscogavialis''
at

Fossilworks Fossilworks was a portal which provides query, download, and analysis tools to facilitate access to the Paleobiology Database, a large relational database assembled by hundreds of paleontologists from around the world. History Fossilworks was cr ...

.org where it coexisted with the much smaller gavialid ''

Sacacosuchus ''Sacacosuchus'' is an extinct monospecific genus of marine gavialid that lived along the coast of the south-east Pacific from approximately 19 to 6.3 million years ago. Its fossils have been found in the Chilcatay Formation, Chilcatay and Pisco ...

''. ''Piscogavialis'' is known only from a single specimen, but it represents some of the best preserved gavialid material known from

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

. The skull is preserved in three dimensions and is nearly complete. A

mandible In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla). The jawbone i ...

and some postcranial material have also been found in association with the skull. Several important features of the

occipital The occipital bone () is a cranial dermal bone and the main bone of the occiput (back and lower part of the skull). It is trapezoidal in shape and curved on itself like a shallow dish. The occipital bone lies over the occipital lobes of the cere ...

region of the skull support a referral to the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Gavialidae Gavialidae is a family of large semiaquatic crocodilians with elongated, narrow snouts. Gavialidae consists of two living species, the gharial (''Gavialis gangeticus'') and the false gharial (''Tomistoma schlegelii''), both occurring in Asia. Man ...

, which also includes the

extant Extant or Least-concern species, least concern is the opposite of the word extinct. It may refer to: * Extant hereditary titles * Extant literature, surviving literature, such as ''Beowulf'', the oldest extant manuscript written in English * Exta ...

gharial The gharial (''Gavialis gangeticus''), also known as gavial or fish-eating crocodile, is a crocodilian in the family (biology), family Gavialidae and among the longest of all living crocodilians. Mature females are long, and males . Adult males ...

and

false gharial The false gharial (''Tomistoma schlegelii''), also known by the names Malayan gharial, Sunda gharial and tomistoma is a freshwater crocodilian of the Family (biology), family Gavialidae native to Peninsular Malaysia, Borneo, Sumatra and Java. It ...

Paleobiology

The strata from which remains of ''Piscogavialis'' have been found suggest that it lived in a coastal environment. Another extinct marine gavialid, ''

'', was described in 2022 and discovered in the same formation. ''

'' was smaller, estimated to be up to long, whereas ''Piscogavialis'' was nearly double the size. During the

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

, what is now the

Pisco Basin Pisco Basin () is a sedimentary basin extending over in southwestern Peru.Solís Mundaca, 2018, p.1 The basin has a 2-kilometre (1.25-mile) thick sedimentary fill, which is about half the thickness of more northern foreland basins in Peru. The o ...

was largely covered by a shallow

marine transgression A marine transgression is a geologic event where sea level rises relative to the land and the shoreline moves toward higher ground, resulting in flooding. Transgressions can be caused by the land sinking or by the ocean basins filling with water ...

that connected to the open ocean. The environment was marked by shallow waters, protected bays with rocky shores and small islands. The south-east Pacific coast was inhabited by at least two species of crocodilians, ''Piscogavialis'' and ''Sacacosuchus'', throughout most of this time period. The remains of both species were found alongside other animals typical for the marine environments of this region including various

cetacea Cetacea (; , ) is an infraorder of aquatic mammals belonging to the order Artiodactyla that includes whales, dolphins and porpoises. Key characteristics are their fully aquatic lifestyle, streamlined body shape, often large size and exclusively c ...

ns, seals, seabirds, marine sloths and sharks. As the Peruvian sediments yielded bones of both adults and juvenile specimens, it is assumed that ''Sacacosuchus'' spent its entire life in saltwater. Although ''Piscogavialis'' was notably larger, it was also likely more specialized, feeding primarily on fast fish. ''Sacacosuchus'', meanwhile, in spite of being only half the length of its contemporary relative, was adapted to a more generalist diet. During the Miocene, environmental factors worked together to highly favor marine

gavialoid Gavialoidea is one of three superfamilies of crocodylians, the other two being Alligatoroidea and Crocodyloidea. Although many extinct species are known, only the gharial ''Gavialis gangeticus'' and the false gharial ''Tomistoma schlegelii'' are ...

s, in particular warm temperatures and abundant shallow water coastal environments suited to their lifestyle. Subsequently, their diversity was high during most of this time period with their range extending as far south as

Chile Chile, officially the Republic of Chile, is a country in western South America. It is the southernmost country in the world and the closest to Antarctica, stretching along a narrow strip of land between the Andes, Andes Mountains and the Paci ...

. However, despite these initially favorable conditions, global temperatures continuously dropped throughout the late

Neogene The Neogene ( ,) is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago ( Mya) to the beginning of the present Quaternary Period million years ago. It is the second period of th ...

. Initially, both ''Piscogavialis'' and ''Sacacosuchus'' weren't heavily affected, with the water temperatures of their habitat continuing to support these

ectotherm An ectotherm (), more commonly referred to as a "cold-blooded animal", is an animal in which internal physiological sources of heat, such as blood, are of relatively small or of quite negligible importance in controlling body temperature.Dav ...

s until at least the end of the Miocene period. Eventually, however, the extinction of Peru's marine gavialids was brought on by the disruption of these coastal ecosystems, caused by dropping sea levels and the uplifting of the

Andes Mountains The Andes ( ), Andes Mountains or Andean Mountain Range (; ) are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is long and wide (widest between 18°S ...

, coupled with the more drastically dropping global temperatures of the

Pliocene The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58

Phylogeny

phylogenetic In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical dat ...

analysis conducted in a 2007 study found

Gryposuchinae Gryposuchinae is an extinct subfamily of gavialid crocodylians. Gryposuchines lived mainly in the Miocene of South America. However, '' "Ikanogavialis" papuensis'' may have survived more recently, into the Late Pleistocene/Holocene. Most were lo ...

to include the genera ''

Aktiogavialis ''Aktiogavialis'' is an extinct genus of crocodylian that lived from the Oligocene until the Miocene in what is now the Caribbean The Caribbean ( , ; ; ; ) is a region in the middle of the Americas centered around the Caribbean Sea in the A ...

'', ''

Gryposuchus ''Gryposuchus'' is an extinct genus of gavialid crocodilian. Fossils have been found from Argentina, Colombia, Venezuela, Brazil and the Peruvian Amazon. The genus existed during the Miocene epoch (Colhuehuapian to Huayquerian). One recently d ...

'', ''

Ikanogavialis ''Ikanogavialis'' is an extinct genus of gavialid crocodilian. Fossils have been found in the Urumaco Formation in Urumaco, Venezuela and the Solimões Formation of Brazil. The strata from which remains are found are late Miocene in age, rath ...

'', ''Piscogavialis'', and ''

Siquisiquesuchus ''Siquisiquesuchus'' (meaning " Siquisique crocodile" after the town in Lara, Venezuela, near where the first described specimens were found) is an extinct genus of gavialid crocodilian. It is known from cranial remains and a few postcranial bon ...

''. Below is a

cladogram A cladogram (from Greek language, Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an Phylogenetic tree, evolutionary tree because it does not s ...

from the 2007 analysis showing the phylogenetic relationships of gryposuchines among

gavialoids Gavialoidea is one of three superfamilies of crocodylians, the other two being Alligatoroidea and Crocodyloidea. Although many extinct species are known, only the gharial ''Gavialis gangeticus'' and the false gharial ''Tomistoma schlegelii'' are ...

: Alternatively, a 2018

tip dating Tip dating is a technique used in molecular dating that allows the inference of time-calibrated phylogenetic trees. Its defining feature is that it uses the ages of the samples to provide time information for the analysis, in contrast with traditio ...

study by Lee & Yates simultaneously using morphological, molecular (

DNA sequencing DNA sequencing is the process of determining the nucleic acid sequence – the order of nucleotides in DNA. It includes any method or technology that is used to determine the order of the four bases: adenine, thymine, cytosine, and guanine. The ...

), and

stratigraphic Stratigraphy is a branch of geology concerned with the study of rock layers (strata) and layering (stratification). It is primarily used in the study of sedimentary and layered volcanic rocks. Stratigraphy has three related subfields: lithost ...

(

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserve ...

age) data indicated that the members of

may in fact be

paraphyletic Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...

and rather an

evolutionary grade A grade is a taxon united by a level of morphological or physiological complexity. The term was coined by British biologist Julian Huxley, to contrast with clade, a strictly phylogenetic unit. Phylogenetics The concept of evolutionary grades ...

towards ''

Gavialis ''Gavialis'' is a genus of crocodylians that includes the living gharial ''Gavialis gangeticus'' and one known extinct species, '' Gavialis bengawanicus.'' ''G. gangeticus'' comes from the Indian Subcontinent, while ''G. bengawanicus'' is know ...

'' and the

, as shown in the cladogram below: The below cladogram is from the 2022 Salas-Gismondi ''et al.'' study describing the newly discovered co-existing ''

'', and shows ''Piscogavialis'' as a more derived member of

References

{{Taxonbar, from=Q7198259, from2=Q112845633 Gavialidae Prehistoric pseudosuchian genera Miocene crocodylomorphs Miocene reptiles of South America Montehermosan Huayquerian Neogene Peru Fossils of Peru Fossil taxa described in 1998