Gavialosuchus
Encyclopedia
Gavialosuchus is an extinct tomistomine from the late Oligocene
and Miocene
of eastern North America
and early Miocene of Europe
. Three species
have been named: the type species
G. eggenburgensis from the early Miocene of Austria
; G. americanus, from the late Miocene
to early Pliocene
of Florida
; and G. carolinensis, from the late Oligocene
of South Carolina
. Another species, as yet unnamed, may be present in the Miocene of Georgia
. Unlike its modern fresh water relatives, Gavialosuchus was an estuarine
and coastal water crocodilian, living in shallow marine waters, living alongside Metaxytherium
, Pomatodelphis, and Hemipristis
serra. It was long-snouted and large: G. carolinensis was at least 5.37 meters long (17.3 ft), and one specimen of G. americanus is estimated at 9.75 metres (32 ft) long based on a 132 centimetres (52 in)-long skull.
As is the case with many fossil taxa, what exactly constitutes Gavialosuchus is not a settled question. Myrick Jr. (2001) proposed synonymizing G. americanus with Thecachampsa antiqua
. Piras et al. (2007) advocated transferring both G. americanus and G. carolinensis to Thecachampsa as distinct species of the latter genus. Jouve et al. (2008) retained G. americanus in Gavialosuchus and found it to be the sister group of G. eggenburgensis (G. carolinensis was not discussed).
Oligocene
The Oligocene is a geologic epoch of the Paleogene Period and extends from about 34 million to 23 million years before the present . As with other older geologic periods, the rock beds that define the period are well identified but the exact dates of the start and end of the period are slightly...
and Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
of eastern North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
and early Miocene of Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
. Three species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
have been named: the type species
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
G. eggenburgensis from the early Miocene of Austria
Austria
Austria , officially the Republic of Austria , is a landlocked country of roughly 8.4 million people in Central Europe. It is bordered by the Czech Republic and Germany to the north, Slovakia and Hungary to the east, Slovenia and Italy to the south, and Switzerland and Liechtenstein to the...
; G. americanus, from the late Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
to early Pliocene
Pliocene
The Pliocene Epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch...
of Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
; and G. carolinensis, from the late Oligocene
Oligocene
The Oligocene is a geologic epoch of the Paleogene Period and extends from about 34 million to 23 million years before the present . As with other older geologic periods, the rock beds that define the period are well identified but the exact dates of the start and end of the period are slightly...
of South Carolina
South Carolina
South Carolina is a state in the Deep South of the United States that borders Georgia to the south, North Carolina to the north, and the Atlantic Ocean to the east. Originally part of the Province of Carolina, the Province of South Carolina was one of the 13 colonies that declared independence...
. Another species, as yet unnamed, may be present in the Miocene of Georgia
Georgia (U.S. state)
Georgia is a state located in the southeastern United States. It was established in 1732, the last of the original Thirteen Colonies. The state is named after King George II of Great Britain. Georgia was the fourth state to ratify the United States Constitution, on January 2, 1788...
. Unlike its modern fresh water relatives, Gavialosuchus was an estuarine
Estuary
An estuary is a partly enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea....
and coastal water crocodilian, living in shallow marine waters, living alongside Metaxytherium
Metaxytherium
Metaxytherium is an extinct genus of dugong that lived from the Miocene to the Pleistocene. Its remains have been found in Africa, Asia, Europe, North America, and South America.- Sources :*Manatees and Dugongs of the World by Jeff Ripple...
, Pomatodelphis, and Hemipristis
Hemipristis
Hemipristis is a genus of weasel shark, family Hemigaleidae. It contains one extant species, the snaggletooth shark , as well as several extinct species.Hemipristis has two distinct type of teeth in each section of its jaw...
serra. It was long-snouted and large: G. carolinensis was at least 5.37 meters long (17.3 ft), and one specimen of G. americanus is estimated at 9.75 metres (32 ft) long based on a 132 centimetres (52 in)-long skull.
As is the case with many fossil taxa, what exactly constitutes Gavialosuchus is not a settled question. Myrick Jr. (2001) proposed synonymizing G. americanus with Thecachampsa antiqua
Thecachampsa
Thecachampsa is an extinct genus of tomistomine crocodilian. Fossils have been found from the eastern United States in deposits that are late Oligocene in age. The type species is T. antiqua. Several other species have been erected. Those named in the 19th century were distinguished primarily by...
. Piras et al. (2007) advocated transferring both G. americanus and G. carolinensis to Thecachampsa as distinct species of the latter genus. Jouve et al. (2008) retained G. americanus in Gavialosuchus and found it to be the sister group of G. eggenburgensis (G. carolinensis was not discussed).