FANDOM


Gryposuchus
Temporal range: Middle – Late Miocene
4f32e6b91f8487de9c794fff90d3f168.jpg
An artist's illustration of Gryposuchus pachakamue
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Crocodilia
Family: Gavialidae
Subfamily: Gryposuchinae
Genus: Gryposuchus
Gurich, 1912
Referred species
  • Gryposuchus colombianus (Langston, 1965)
  • Gryposuchus croizati (Riff and Aguilera, 2008)
  • Gryposuchus jessei (Gurich, 1912)
  • Gryposuchus neogaeus (Burmeister, 1885) [originally Ramphostoma neogaeus] (type)
  • Gryposuchus pachakamue (Salas-Gismondi et al., 2016)
Synonyms
  • Ramphostoma neogaeus (Burmeister, 1885 )

Gryposuchus is an extinct genus of gavialoid crocodilian. It is the type genus of the subfamily Gryposuchinae.Fossils have been found from Argentina, Colombia, Venezuela, Braziland the Peruvian Amazon. The genus existed during the early and middleMiocene epoch. One recently describedspecies, G. croizati, grew to an estimated length of 11.4 metres (37 ft).

Species Edit

The type species of Gryposuchus is G. neogaeus. Specimens from this species were first described from Argentina in 1885, although it was referred toRamphostoma at the time. It was assigned to the current genus in 1912 along with a newly described species, G. jessei.

Another species, G. colombianus, has been recovered from deposits in Colombia that date back to the Miocene and Pliocene epochs. This species, named in 1965, was originally referred to Gavialis. Fragmentary material ofGryposuchus from the Fitzcarrald Archin the Peruvian Amazon dating back to the late middle Miocene bear a close resemblance to G. colombianus, but differ in rostrum proportions.

Some skull material also recovered from Peruvian Amazon (Iquitos) in the Pebas Formation, has been named asGryposuchus pachakamue in 2016 by Roberto Salas-Gismondi et al. It includes the holotype MUSM 987, a well preserved skull that lacks of temporal and occipital bones; it measures 623.2 millimeters in length, and a series of referred specimens, including possible juveniles. The species was named after the Quechuan word for a primordial god and "storyteller". This new species is characterized by have 22 teeth in the mandible and the maxilla, a snout comparable in relative length to the modern Gavialis gangeticus, and is notable since that its orbits were wider than long and not so upturned as another species of gavialids, including the gryposuchines, which implies that G. pachakamue doesn't had the "telescoped" orbits (protruding eyes) condition fully developed. Since that it species, that inhabited the proto-Amazon fluvial system 13 million years ago, is the oldest record of gavialids in this area and it had a primitive telescoped eyes condition, it shows that the development of such condition was a case of convergent evolution with the species of Gavialis also found in fluvial environments.

220px-Large crocodyliformes 2015

Scale diagram showing the size of G. croizati (light blue)

A species described in 2008, G. croizati, found from the upper Miocene Urumaco Formation in northwestern Venezuela, can be distinguished from other species of Gryposuchus on the basis of a reduced number of maxillary teeth, a slender parietal interfenestral bar, and widely separated and reduced palatinefenestrae, among other things. Based on measurements of the orbital cranial skeleton, the length of the animal has been estimated at around 11.4 m in length, with a total mass of about 1745 kg. Measuring the entire length of the skull from the end of the rostrum to the supraoccipital would result in a much larger size estimate, up to three times as great. However, because there is considerable variation seen in rostral proportions among crocodilians, the latter measurements are probably not an accurate way of estimating body mass and length. Despite this, the species is still one of the largest crocodilians known to have existed, and it may indeed have been the largest gavialoid to have ever existed if a recent revision in the estimated size of the large tomistomine Rhamphosuchus is correct (the genus was once considered to be 15 m in length; the new estimate puts it at approximately 10 m).

Paleobiology Edit

Some gryposuchines such asSiquisiquesuchus and Piscogavialis have been found from localities thought to have been deposited in coastal environments. The presence ofGryposuchus in the Urumaco Formation of Venezuela, which does include marine strata, lends credence to the idea that gryposuchines may have been living in coastal environments. However, certain localities where material from the species G. colombianus has been recovered, such as La Venta, Colombia, were clearly deposited in non-marine environments, speaking against the proposed coastal lifestyle hypothesis for all gryposuchines.

Ad blocker interference detected!


Wikia is a free-to-use site that makes money from advertising. We have a modified experience for viewers using ad blockers

Wikia is not accessible if you’ve made further modifications. Remove the custom ad blocker rule(s) and the page will load as expected.