Gryposuchinae

Last updated

Gryposuchinae
Temporal range: Middle Oligocene - Holocene, 28–0.117  Ma
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Crocodilia
Family: Gavialidae
Subfamily:† Gryposuchinae
Vélez-Juarbe et al., 2007
Genera

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.

Contents

Description

Gryposuchines had long, narrow snouts and protruding eye sockets. One distinguishing feature of the group is the lack of a large exposure of the prootic bone around the trigeminal foramen, a hole in the side of the braincase wall. [1]

Classification

Gryposuchinae was named in 2007 as a subfamily of closely related gavialid crocodilians. It was cladistically defined as a stem-based taxon including Gryposuchus jessei and all crocodilians more closely related to it than to Gavialis gangeticus (the gharial) or Tomistoma schlegelii (the False gharial). [1] The tomistomines (including the living false gharial) were long thought to be classified as crocodiles and not closely related to gavialoids. [2] However, recent molecular studies using DNA sequencing have consistently indicated that the false gharial (Tomistoma) (and by inference other related extinct forms in Tomistominae) actually belong to Gavialoidea (and Gavialidae). [3] [4] [5] [6] [7] [8] [9]

A phylogenetic analysis conducted in the 2007 study found Gryposuchinae to include the genera Aktiogavialis, Gryposuchus, Ikanogavialis , Piscogavialis , and Siquisiquesuchus . The below cladogram is from the 2007 analysis showing the phylogenetic relationships of gryposuchines among gavialoids. [1] Hesperogavialis was excluded due to a lack of skull material, and Dadagavialis due to its 2018 discovery. [10]

Gavialoidea  

Eothoracosaurus

Thoracosaurus

Eosuchus

Argochampsa

Gavialidae  

Eogavialis

Gavialis

Gryposuchinae 

Ikanogavialis

Piscogavialis

Siquisiquesuchus

Gryposuchus

Aktiogavialis

Alternatively, phylogenetic studies recovering the tomistomines (including the living false gharial) within Gavialidae have indicated that the members of Gryposuchinae and the genus Gryposuchus may in fact be paraphyletic and rather an evolutionary grade towards Gavialis and the gharial, [11] [8] as shown in the cladogram below: [11]

Gavialidae
Tomistominae

Paratomistoma courti †

Tomistoma schlegelii False gharial

Toyotamaphimeia machikanensis †

Penghusuchus pani †

"Tomistoma" cairense †

Thoracosaurus isorhynchus †

Eosuchus lerichei †

Eosuchus minor †

Portugalosuchus azenhae †

Eothoracosaurus mississippiensis †

Thoracosaurus neocesariensis †

"Tomistoma" dowsoni †

Eogavialis africanum †

Aktiogavialis caribesi †

Argochampsa krebsi †

Piscogavialis jugaliperforatus †

Ikanogavialis gameroi †

Siquisiquesuchus venezuelensis †

Dadagavialis gunai †

"Gryposuchinae"

Gryposuchus colombianus †

Gryposuchus pachakamue †

Gryposuchus neogaeus †

Gryposuchus croizati †

Gavialis lewisi †

Gavialis browni †

Gavialis gangeticus Gharial

traditional Gryposuchinae

Paleobiology

The subfamily Gryposuchinae are the sole members of the superfamily Gavialoidea to occupy South America, the duration of which is entirely limited to the Miocene. However, although most of their history is recorded on the continent, dispersion was achieved via a prior presence in the Caribbean (Aktiogavialis, the oldest known gryposuchine, from in the Middle Oligocene of Puerto Rico, and Dadagavialis in the Early Miocene of Panama, respectively). [1] [12] Furthermore, indeterminate gavialoid remains have recovered from the Oligo-Miocene boundary of coastal Brazil. [13] The origin of these gryposuchines is unclear, although traditionally, an African origin has been favoured as 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.

Gryposuchus , Ikanogavialis and Siquisiquesuchus represent the first known members of Gryposuchinae in Early Miocene of South America, colonizing around Colombia and Venezuela. Additionally, indeterminate finds of gavialoids (all in either coastal or marine sediments) are present in early Miocene Jimol Formation and for the early/middle Miocene Castilletes Formation in Colombia, [14] [15] and from the Oligo-Miocene boundary Pirabas Formation of coastal Brazil, [13] Gryposuchus and Ikanogavialis persist into the Middle Miocene, with the freshwater-adapting Gryposuchus expanding throughout the Pebas mega-wetlands into inland Peru and Argentina. In the Late Miocene, Gryposuchinae diversity explodes, with Gryposuchus and Ikanogavialis being joined by Hesperogavialis, of Venezuela and Brazil, Piscogavialis of coastal Peru, and Aktiogavialis, re-appearing in the fossil record once more, also in Venezuela. At this point, five of the seven genera are present in the Late Miocene, with four genera overlapping in the Urumaco Formation of Venezuela alone, a particular hotspot for crocodilian diversity in the Miocene. Based on the deposits in which they were found, most genera of gryposuchines were solely estuarine, coastal or marine-dwelling; only the genera Gryposuchus and Hesperogavialis had some level of freshwater presence. On the flipside, whereas most gryposuchines were restricted to a certain coastal region and time period, Gryposuchus enjoyed a continent wide distribution, spread from Andeo-Venezuelan drainage basin to Argentina from the Middle Miocene onwards. Additionally, whereas the other genera had one or two species each, Gryposuchus had five, one of which (G. croizati) was the largest of the superfamily on record, at an estimated length of 10m. [16]

At the Miocene/Pliocene boundary, all gryposuchines, and thus the entire superfamily of Gavialoidea, along with the first wave of crocodyloids (Brasilosuchus and Charactosuchus, which also colonized during the Miocene) were likely extirpated from South America, with Caimaninae undergoing a severe reduction in size and diversity as well. This was likely due to the continuing elevation of the northern sections of the Andes chain reshaping the future Amazonian drainage system, re-rerouting flow to the Venezuelan Caribbean to the much cooler Atlantic, and transforming the mega-wetlands into a fully developed riverine system. The co-current aridification of the continental interior, and isolation of the peripheral wetland basins, also restricted the space and food resources of these large, food intensive specialist crocodilians, and has thus also been suggested as an essential factor in their extinction. [15] [17] [18] Several other gavialid taxa also went extinct globally, suggesting a major global climate change event. However, there may be evidence that Piscogavialis survived this mass extinction, persisting on the Pacific coast of Pliocene Peru for a few million more years. [19] Furthermore, crocodyloids would recolonize South America via the African Crocodylus in the early Pliocene, [15] whereas gryposuchines would only re-appear in the fossil record six million years later, as "Ikanogavialis" papuensis, in the Late Pleistocene/Holocene marine sediments of the Woodlark Island, in the Solomon Sea. Separated by a geographical barrier of at least 10,000 km, this gavialoid had presumably reached Melanesia in a similar fashion as Brachylophus and Lapitiguana iguanas, being carried by Pacific oceanic currents. Found in association with dugongs and sea turtles, "Ikanogavialis" papuensis was a marine animal like its ancestors, a 2-3 meter long coastal piscivore so far known only from Murua. Like other Pleistocene gharials, the species was presumably hunted to extinction by humanity. [20]

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>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>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.

<i>Aktiogavialis</i> Species of reptile (fossil)

Aktiogavialis is an extinct genus of crocodylian that lived from the Oligocene until the Miocene in what is now the Caribbean. Two species have been described: Aktiogavialis puertoricensis from the Middle Oligocene of Puerto Rico and Aktiogavialis caribesi from the Huayquerian of the Late Miocene of Venezuela.

Dollosuchoides, colloquially known as the Crocodile of Maransart, is an extinct monospecific genus of gavialoid crocodilian, traditionally regarded as a member of the subfamily Tomistominae. Fossils have been found in the Brussel Formation of Maransart, Belgium and date back to the middle Eocene.

Eogavialis is an extinct genus of eusuchian crocodylomorph, usually regarded as a gavialoid crocodylian. It superficially resembles Tomistoma schlegelii, the extant false gharial, and consequently material from the genus was originally referred to Tomistoma. Indeed, it was not until 1982 that the name Eogavialis was constructed after it was realised that the specimens were from a more basal form.

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

Eothoracosaurus is an extinct monospecific genus of eusuchian crocodylomorphs found in Eastern United States which existed during the Late Cretaceous period. Eothoracosaurus is considered to belong to an informally named clade called the "thoracosaurs", named after the closely related Thoracosaurus. Thoracosaurs in general were traditionally thought to be related to the modern false gharial, largely because the nasal bones contact the premaxillae, but phylogenetic work starting in the 1990s instead supported affinities within gavialoid exclusive of such forms. Even more recent phylogenetic studies suggest that thoracosaurs might instead be non-crocodilian eusuchians.

<i>Gryposuchus</i> Extinct genus of gavialoid crocodilian

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. One recently described species, G. croizati, grew to an estimated length of 10 metres (33 ft). Gryposuchus is the type genus of the subfamily Gryposuchinae, although a 2018 study indicates that Gryposuchinae and Gryposuchus might be paraphyletic and rather an evolutionary grade towards the gharial.

Hesperogavialis is an extinct genus of gryposuchine gavialid. Fossils have been found from Venezuela and Brazil that date back to the Middle to Late Miocene. Although Hesperogavialis is one of the best known gavialoids from South America, the posterior portion of the skull is still unknown, making any attempts at classification within the family somewhat more difficult than other gavialoids in which much of the skull is present. The genus possibly comprises three species. The type species, H. cruxenti, has been found in the Urumaco Formation in Venezuela. A second possible species, named H. bocquentini, has been described from the Solimões Formation in Acre, Brazil, and can be distinguished from H. cruxenti by the asymmetry seen in the anterior portion of the nasals and the small distance between alveoli. A third species can be recognized from the same locality in Acre, although a formal name has yet to be given to it.

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.

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

Kentisuchus is an extinct genus of gavialoid crocodylian, traditionally regarded as a member of the subfamily Tomistominae. Fossils have been found from England and France that date back to the early Eocene. The genus has also been recorded from Ukraine, but it unclear whether specimens from Ukraine are referable to Kentisuchus.

Maroccosuchus zennaroi is an extinct gavialoid crocodylian from the Early Eocene of Morocco, traditionally regarded as a member of the subfamily Tomistominae.

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.

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

Piscogavialis is an extinct monospecific genus of gryposuchine gavialid crocodylian. The only species yet known is P. jugaliperforatus. Fossils of Piscogavialis have been found from the Mio-Pliocene Pisco Formation of the Sacaco Basin in southern Peru in 1998, where it coexisted with the much smaller gavialid Sacacosuchus.

Siquisiquesuchus is an extinct genus of gavialid crocodilian. It is known from cranial remains and a few postcranial bones found in Miocene-age rocks of the Castillo Formation in northwestern Venezuela.

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

Penghusuchus is an extinct genus of gavialid crocodylian. It is known from a skeleton found in Middle to Upper Miocene rocks of Penghu Island, off Taiwan. The taxon was described in 2009 by Shan and colleagues; the type species is P. pani. It may be related to two other fossil Asian gavialids: Toyotamaphimeia machikanensis of Japan and Hanyusuchus sinensis of South China. It was a medium-sized gavialid with an estimated total length of 4.5 metres (15 ft).

<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.

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.

Dadagavialis is an extinct monospecific genus of gavialid crocodylian that lived during the Early Miocene in what is now Panama. It was described in 2018, and was proposed to be a member of Gryposuchinae. However, other studies have shown Gryposuchinae to be paraphyletic and rather an evolutionary grade towards the living gharial, and thus Dadagavialis might just be classified as a member of Gavialidae.

References

  1. 1 2 3 4 Vélez-Juarbe, Jorge; Brochu, C.A.; Santos, H. (2007). "A gharial from the Oligocene of Puerto Rico: transoceanic dispersal in the history of a non-marine reptile". Proceedings of the Royal Society B. 274 (1615): 1245–1254. doi:10.1098/rspb.2006.0455. PMC   2176176 . PMID   17341454.
  2. ↑ Brochu, C.A.; Gingerich, P.D. (2000). "New tomistomine crocodylian from the Middle Eocene (Bartonian) of Wadi Hitan, Fayum Province, Egypt". University of Michigan Contributions from the Museum of Paleontology. 30 (10): 251–268.
  3. ↑ Harshman, J.; Huddleston, C. J.; Bollback, J. P.; Parsons, T. J.; Braun, M. J. (2003). "True and false gharials: A nuclear gene phylogeny of crocodylia" (PDF). Systematic Biology. 52 (3): 386–402. doi: 10.1080/10635150309323 . PMID   12775527.
  4. ↑ Gatesy, Jorge; Amato, G.; Norell, M.; DeSalle, R.; Hayashi, C. (2003). "Combined support for wholesale taxic atavism in gavialine crocodylians" (PDF). Systematic Biology. 52 (3): 403–422. doi: 10.1080/10635150309329 . PMID   12775528.
  5. ↑ Willis, R. E.; McAliley, L. R.; Neeley, E. D.; Densmore Ld, L. D. (June 2007). "Evidence for placing the false gharial (Tomistoma schlegelii) into the family Gavialidae: Inferences from nuclear gene sequences". Molecular Phylogenetics and Evolution. 43 (3): 787–794. doi:10.1016/j.ympev.2007.02.005. PMID   17433721.
  6. ↑ Gatesy, J.; Amato, G. (2008). "The rapid accumulation of consistent molecular support for intergeneric crocodylian relationships". Molecular Phylogenetics and Evolution . 48 (3): 1232–1237. doi:10.1016/j.ympev.2008.02.009. PMID   18372192.
  7. ↑ Erickson, G. M.; Gignac, P. M.; Steppan, S. J.; Lappin, A. K.; Vliet, K. A.; Brueggen, J. A.; Inouye, B. D.; Kledzik, D.; Webb, G. J. W. (2012). Claessens, Leon (ed.). "Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and tooth-pressure experimentation". PLOS ONE. 7 (3): e31781. Bibcode:2012PLoSO...731781E. doi: 10.1371/journal.pone.0031781 . PMC   3303775 . PMID   22431965.
  8. 1 2 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.
  9. ↑ Hekkala, E.; Gatesy, J.; Narechania, A.; Meredith, R.; Russello, M.; Aardema, M. L.; Jensen, E.; Montanari, S.; Brochu, C.; Norell, M.; Amato, G. (2021-04-27). "Paleogenomics illuminates the evolutionary history of the extinct Holocene "horned" crocodile of Madagascar, Voay robustus". Communications Biology. 4 (1): 505. doi: 10.1038/s42003-021-02017-0 . ISSN   2399-3642. PMC   8079395 . PMID   33907305.
  10. ↑ Salas-Gismondi, Rodolfo; Moreno-Bernal, Jorge W.; Scheyer, Torsten M.; Sánchez-Villagra, Marcelo R.; Jaramillo, Carlos (2019-06-18). "New Miocene Caribbean gavialoids and patterns of longirostry in crocodylians". Journal of Systematic Palaeontology. 17 (12): 1049–1075. doi:10.1080/14772019.2018.1495275. ISSN   1477-2019. S2CID   91495532.
  11. 1 2 Rio, Jonathan P.; Mannion, Philip D. (6 September 2021). "Phylogenetic analysis of a new morphological dataset elucidates the evolutionary history of Crocodylia and resolves the long-standing gharial problem". PeerJ . 9: e12094. doi: 10.7717/peerj.12094 . PMC   8428266 . PMID   34567843.
  12. ↑ Salas-Gismondi, Rodolfo; Moreno-Bernal, Jorge W.; Scheyer, Torsten M.; Sánchez-Villagra, Marcelo R.; Jaramillo, Carlos (2019-06-18). "New Miocene Caribbean gavialoids and patterns of longirostry in crocodylians". Journal of Systematic Palaeontology. 17 (12): 1049–1075. doi:10.1080/14772019.2018.1495275. ISSN   1477-2019. S2CID   91495532.
  13. 1 2 Moraes-Santos, Heloisa; Villanueva, Jean Bocquentin; Toledo, Peter Mann (2011-12-01). "New remains of a gavialoid crocodilian from the late Oligocene−early Miocene of the Pirabas Formation, Brazil". Zoological Journal of the Linnean Society. 163 (suppl_1): S132–S139. doi: 10.1111/j.1096-3642.2011.00710.x . ISSN   0024-4082.
  14. ↑ Cidade, Giovanne; Fortier, Daniel; Hsiou, Annie (2018-12-01). "The crocodylomorph fauna of the cenozoic of South America and its evolutionary history: A review". Journal of South American Earth Sciences. 90: 392–411. doi:10.1016/j.jsames.2018.12.026. S2CID   134902094.
  15. 1 2 3 Moreno-Bernal, Jorge W.; Head, Jason; Jaramillo, Carlos A. (2016-05-03). "Fossil Crocodilians from the High Guajira Peninsula of Colombia: Neogene faunal change in northernmost South America". Journal of Vertebrate Paleontology. 36 (3): e1110586. doi:10.1080/02724634.2016.1110586. ISSN   0272-4634. S2CID   130332367.
  16. ↑ Cidade, Giovanne; Fortier, Daniel; Hsiou, Annie (2018-12-01). "The crocodylomorph fauna of the cenozoic of South America and its evolutionary history: A review". Journal of South American Earth Sciences. 90: 392–411. doi:10.1016/j.jsames.2018.12.026. S2CID   134902094.
  17. ↑ Cidade, Giovanne; Fortier, Daniel; Hsiou, Annie (2018-12-01). "The crocodylomorph fauna of the cenozoic of South America and its evolutionary history: A review". Journal of South American Earth Sciences. 90: 392–411. doi:10.1016/j.jsames.2018.12.026. S2CID   134902094.
  18. ↑ "Fourteen closely related crocodiles existed around 5 million years ago". ScienceDaily. Retrieved 2020-04-19.
  19. ↑ Salas-Gismondi, Rodolfo; Moreno-Bernal, Jorge W.; Scheyer, Torsten M.; Sánchez-Villagra, Marcelo R.; Jaramillo, Carlos (2019-06-18). "New Miocene Caribbean gavialoids and patterns of longirostry in crocodylians". Journal of Systematic Palaeontology. 17 (12): 1049–1075. doi:10.1080/14772019.2018.1495275. ISSN   1477-2019. S2CID   91495532.
  20. ↑ Molnar, R. E. 1982. A longirostrine crocodilian from Murua (Woodlark), Solomon Sea. Memoirs of the Queensland Museum 20, 675-685.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.