Gavialis bengawanicus

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Gavialis bengawanicus
Gavialis bengawanicus skull.png
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Crocodilia
Family: Gavialidae
Genus: Gavialis
Species:
G. bengawanicus
Binomial name
Gavialis bengawanicus
Dubois, 1908

Gavialis bengawanicus is an extinct species of crocodilian that is related to the modern Indian gharial. [1] Fossils have been found in Thailand and Indonesia. The type locality is at Trinil. [2]

The presence of this species in Thailand may provide an explanation for the distribution of fossil gharials that appears disjunct, covering Pakistan and Java but not the connecting areas. The fossils suggest that gharials may have dispersed from Indo-Pakistan to Indonesia through Thailand without having to resort to marine routes. [3]

Below is a cladogram that shows the proposed phylogeny within Gavialidae, including extinct members, and how Gavialis bengawanicus is most closely related to the living gharial: [4]

Gavialidae

Gavialis gangeticus Gharial

Gavialis bengawanicus

Gavialis browni

Gryposuchus colombianus

Ikanogavialis

Gryposuchus pachakamue

Piscogavialis

Harpacochampsa

Toyotamaphimeia

Penghusuchus

Gavialosuchus

Tomistoma lusitanicum

Tomistoma schlegelii False gharial

Related Research Articles

<span class="mw-page-title-main">Gavialinae</span> Subfamily of gharial crocodylians

Gavialinae is a subfamily of large semiaquatic crocodilian reptiles, resembling crocodiles, but with much thinner snouts. Gavialinae is one of the two major subfamilies within the family Gavialidae - the other being the subfamily Tomistominae, which contains the false gharial and extinct relatives.

<span class="mw-page-title-main">Gavialidae</span> Family of gharial crocodylians

Gavialidae is a family of large semiaquatic crocodilians with elongated, narrow snouts. Gavialidae consists of two living species, the gharial and the false gharial, both occurring in Asia. Many extinct members are known from a broader range, including the recently extinct Hanyusuchus. Gavialids are generally regarded as lacking the jaw strength to capture the large mammalian prey favoured by crocodiles and alligators of similar size so their thin snout is best used to catch fish, however the false gharial has been found to have a generalist diet with mature adults preying upon larger vertebrates, such as ungulates.

<i>Gavialis</i> Genus of reptiles

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 known from Java. Gavialis likely first appeared in the Indian Subcontinent in the Pliocene and dispersed into the Malay Archipelago through a path called the Siva–Malayan route in the Quaternary. Remains attributed to Gavialis have also been found on Sulawesi and Woodlark Island east of the Wallace Line, suggesting a prehistoric lineage of Gavialis was able to traverse marine environments and reach places possibly as far as western Oceania.

<span class="mw-page-title-main">Gharial</span> Crocodilian native to the Indian subcontinent

The gharial, also known as gavial or fish-eating crocodile, is a crocodilian in the family Gavialidae and among the longest of all living crocodilians. Mature females are 2.6 to 4.5 m long, and males 3 to 6 m. Adult males have a distinct boss at the end of the snout, which resembles an earthenware pot known as a ghara, hence the name "gharial". The gharial is well adapted to catching fish because of its long, narrow snout and 110 sharp, interlocking teeth.

<span class="mw-page-title-main">False gharial</span> Species of crocodilian

The false gharial, also known by the names Malayan gharial,Sunda gharial and tomistoma is a freshwater crocodilian of the family Gavialidae native to Peninsular Malaysia, Borneo, Sumatra and Java. It is listed as Vulnerable on the IUCN Red List, as the global population is estimated at around 2,500 to 10,000 mature individuals.

<i>Tomistoma</i> Genus of crocodilians

Tomistoma is a genus of gavialid crocodilians. They are noted for their long narrow snouts used to catch fish, similar to the gharial. Tomistoma contains one extant (living) member, the false gharial, as well as potentially several extinct species: T. cairense, T. lusitanicumT. coppensi, and T. dowsoni. However, these species may need to be reclassified to different genera as studies have shown them to be paraphyletic, for example: previously assigned species T. taiwanicus from Taiwan, is reclassified to the genus Toyotamaphimeia, and T. dowsoni should be excluded from Tomistoma based on phylogenetic analysis.

<i>Rhamphosuchus</i> Extinct genus of reptiles

Rhamphosuchus is an extinct genus of gavialid crocodylians. It lived during the Pliocene and its fossils have been found in two regions; the Siwalik Hills of Pakistan and India as well as the Sindh region of Pakistan. Its type species is Rhamphosuchus crassidens, which is only known from incomplete sets of fossils, mostly teeth and skulls. Four species traditionally placed in the genus Gavialis may be included as well.

<i>Gavialosuchus</i> Extinct genus of reptiles

Gavialosuchus is an extinct genus of gavialoid crocodylian from the early Miocene of Europe. Currently only one species is recognized, as a few other species of Gavialosuchus have since been reclassified to other genera.

<span class="mw-page-title-main">Alligatoroidea</span> Superfamily of reptiles

Alligatoroidea is one of three superfamilies of crocodylians, the other two being Crocodyloidea and Gavialoidea. Alligatoroidea evolved in the Late Cretaceous period, and consists of the alligators and caimans, as well as extinct members more closely related to the alligators than the two other groups.

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, rather than Pliocene as was once thought. A possible member of this genus survived into the Late Holocene on Muyua or Woodlark Island in Papua New Guinea.

Paratomistoma is an extinct monospecific genus of gavialoid crocodylian. It is based on the holotype specimen CGM 42188, a partial posterior skull and lower jaw discovered at Wadi Hitan, Egypt, in Middle Eocene-age rocks of the Gehannam Formation. The skull is unfused but considered morphologically mature. Paratomistoma was named in 2000 by Christopher Brochu and Philip Gingerich; the type species is P. courti in honor of Nicholas Court, who found CGM 42188. They performed a phylogenetic analysis and found Paratomistoma to be a derived member of Tomistominae, related to the false gharial. It may have been a marine or coastal crocodilian.

<span class="mw-page-title-main">Crocodyloidea</span> Superfamily of crocodiles

Crocodyloidea is one of three superfamilies of crocodilians, the other two being Alligatoroidea and Gavialoidea, and it includes the crocodiles. Crocodyloidea may also include the extinct Mekosuchinae, native to Australasia from the Eocene to the Holocene, although this is disputed.

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 long-snouted coastal forms. The group was named in 2007 and includes genera such as Gryposuchus and Aktiogavialis, although a 2018 study indicates that the group might be paraphyletic and rather an evolutionary grade towards the gharial.

<span class="mw-page-title-main">Gavialoidea</span> Superfamily of large reptiles

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 alive today, with Hanyusuchus having become extinct in the last few centuries.

<span class="mw-page-title-main">Tomistominae</span> Subfamily of reptiles

Tomistominae is a subfamily of crocodylians that includes one living species, the false gharial. Many more extinct species are known, extending the range of the subfamily back to the Eocene epoch. In contrast to the false gharial, which is a freshwater species that lives only in southeast Asia, extinct tomistomines had a global distribution and lived in estuaries and along coastlines.

<span class="mw-page-title-main">Brevirostres</span> Taxon of reptiles

Brevirostres is a paraphyletic group of crocodilians that included alligatoroids and crocodyloids. Brevirostres are crocodilians with small snouts, and are distinguished from the long-snouted gharials. It is defined phylogenetically as the last common ancestor of Alligator mississippiensis and Crocodylus niloticus and all of its descendants. This classification was based on morphological studies primarily focused on analyzing skeletal traits of living and extinct fossil species, and placed the gharials outside the group due to their unique skull structure, and can be shown in the simplified cladogram below:

Crocodylus palaeindicus is an extinct species of crocodile from southern Asia. C. palaeindicus lived from the Miocene to the Pliocene. It may be an ancestor of the living Mugger crocodile.

<i>Gavialis browni</i> Extinct species of reptile

Gavialis browni is an extinct species of the crocodylian genus Gavialis and a close relative of the living gharial Gavialis gangeticus.

Tomistoma cairense is an extinct species of gavialoid crocodilian from the Lutetian stage of the Eocene era. It lived in North East Africa, especially Egypt. Remains of T. cairense have been found in the Mokattam Formation, in Mokattam, Egypt. Tomistoma cairense did not have a Maxilla process within their lacrimal gland, whereas all extant (living) crocodilians do.

<span class="mw-page-title-main">Longirostres</span> Clade of crocodilians

Longirostres is a clade of crocodilians that includes the crocodiles and the gavialids, to the exclusion of the alligatoroids. Defined in 2003 by Harshman et al., Longirostres is a crown group defined phylogenetically as including the last common ancestor of Crocodylus niloticus and Gavialis gangeticus and all of its descendants.

References

  1. Delfino, M. & De Vos, J. (2010). "A revision of the Dubois crocodylians, Gavialis bengawanicus and Crocodylus ossifragus, from the Pleistocene Homo erectus beds of Java". Journal of Vertebrate Paleontology. 30 (2): 427–441. doi:10.1080/02724631003617910. S2CID   86396515.
  2. "Gavialis bengawanicus". Paleo-Database.
  3. Martin, J. E.; Buffetaut, E.; Naksri, W.; Lauprasert, K. & Claude, J. (2012). "Gavialis from the Pleistocene of Thailand and its relevance for drainage connections from India to Java". PLOS ONE. 7 (9): e44541. doi: 10.1371/journal.pone.0044541 . PMC   3445548 . PMID   23028557.
  4. Michael S. Y. Lee; Adam M. Yates (27 June 2018). "Tip-dating and homoplasy: reconciling the shallow molecular divergences of modern gharials with their long fossil". Proceedings of the Royal Society B . 285 (1881). doi: 10.1098/rspb.2018.1071 . PMC   6030529 . PMID   30051855.