Synonyms for aktiogavialis or Related words with aktiogavialis
Examples of "aktiogavialis"
is an extinct genus of crocodylian from the Oligocene epoch some 30 million years ago. Only one species in the genus, "
puertoricensis", has been described so far.
Gavialoidea contains the family Gavialidae and several more basal extinct forms such as "Thoracosaurus" and "Eosuchus". Within Gavialidae are two subfamilies: Gavialinae, which includes the living gharial, and Gryposuchinae, which includes several extinct forms such as "Gryposuchus" and "
A phylogenetic analysis conducted in the 2007 study found Gryposuchinae to include the genera "
", "Gryposuchus", "Ikanogavialis", "Piscogavialis", and "Siquisiquesuchus". Below is a cladogram from the 2007 analysis showing the phylogenetic relationships of gryposuchines among gavialoids:
The origin of gryposuchines is unclear. Earlier gavialids that were their probable ancestors are known from Africa and Asia. Traditionally, an African origin has been favored because gavialids would have been more likely to cross the Atlantic Ocean than the longer expanses of the Pacific Ocean. Moreover, warm equatorial currents run across the Atlantic from Africa to the Americas, assisting in travel. The presence "
" in the Caribbean supports an Atlantic migration. Being the oldest known gryposuchine, "
" was likely in the closest position to the time and location of the radiation.
As a typical gavialoid, "
" followed the standard crocodilian body plan. An elongated, squat quadrupedal body terminated in a long, laterally flattened tail at one end, and a specialized, narrow snout at the other. As with the other members of its family, the snout of "
" was extremely long and narrow, tapering into a thin structure past the eye sockets. Based on the fragmentary remains recovered, the species was differentiated from other members of its family by unique positioning and geometry of its skull elements. Phylogenetic analysis indicates its closest relatives were the extinct gavials "Gryposuchus" and "Siquisiquesuchus".
The genus' name, "
", is derived from the Greek words "aktios" (river) and "gavialis" (gavial). This roughly translates to "shore gavial", referring to its rather estuarine distribution. The specific name "puertoricensis" means "from Puerto Rico", in reference to the specimen's country of origin.
Gryposuchinae is an extinct subfamily of gavialid crocodylians. Gryposuchines lived mainly in South America during the Oligocene and Miocene epochs, though ""Gavialis" papuensis" survived more recently into the Late Pleistocene/Holocene. Most were long-snouted coastal forms. The group was named in 2007 and includes genera such as "Gryposuchus" and "
The type species of the genus, "A. puertoricensis", was described in 2007. The holotype, designated UPRMP 3094, was discovered in Puerto Rican deposits dating from the Oligocene epoch some 30 million years old. The deposits, part of the San Sebastián Formation along the Río Guatemala in Puerto Rico, have been an adequate supply of other crocodylian fossils. "
" remains recovered were extremely fragmentary, consisting of an incomplete skull featuring elements of the braincase and other scattered cranial elements.
Marine sediments and nanofossils form part of the deposits where the specimen was found, indicating a marine distribution for ". puertoricensis". This is in contrast with the living gavialoids, which reside entirely in the freshwater rivers of South Asia. While fossils found in prehistoric deltaic sediments possibly have been washed onto the delta from inland sources, the "
" specimen found so far was from a location that had essentially been islandic. This has led to conclusions that gavialoids were partially or primarily saltwater reptiles prior to the evolution of the group's one or two extant species.
The earliest gharial may have been related to the modern types. Some died out at the same time as the dinosaurs at the end of the Cretaceous, others survived until the early Eocene. The modern forms appeared at much the same time, evolving in the estuaries and coastal waters of Africa, and crossing the Atlantic to reach South America as well. The discovery of the fossil remains of the Puerto Rican gharial "
puertorisensis" in a cave located in San Sebastián, Puerto Rico, suggested that the Caribbean served as the link between the two continents.
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