Araripesuchus

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Araripesuchus
Temporal range: Early - Late Cretaceous, 125–66  Ma
Araripesuchus.jpg
Skull of A. wegeneri from different angles
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Clade: Archosauria
Clade: Pseudosuchia
Clade: Crocodylomorpha
Clade: Crocodyliformes
Clade: Notosuchia
Family: Uruguaysuchidae
Genus: Araripesuchus
Price, 1959
Species
  • A. gomesiiPrice, 1959 (type)
  • A. wegeneriBuffetaut, 1981
  • A. patagonicusOrtega et al., 2000
  • A. buitreraensisPol & Apesteguia, 2005
  • A. tsangatsanganaTurner, 2006
  • A. rattoides Sereno & Larsson, 2009

Araripesuchus is a genus of extinct crocodyliform that existed during the Cretaceous period of the late Mesozoic era some 125 to 66 million years ago. [1] [2] Six species of Araripesuchus are currently known. They are generally considered to be notosuchians (belonging to the clade Mesoeucrocodylia), characterized by their varied teeth types and distinct skull elements. [3] This genus consists of six species: A. buitreraensis, discovered in Argentina, A. wegeneri, discovered in Cameroon and Niger, A. rattoides, discovered in Niger, A. tsangatsangana, discovered in Madagascar, A. gomesii (the type species), discovered in Brazil and another species discovered in Argentina, A. patagonicus. [4] It has been argued that the phylogenetic position of this genus is uncertain, and that taxonomic revision is required.

Description

A. wegeneri is estimated to reach 81 centimetres (32 in) long while A. rattoides is estimated to reach up to 1 metre (3.3 ft). [5] Araripesuchus can be distinguished by their laterally bulged edges of the snout, with the bulge being the most prominent around the area of an enlarged maxillary tooth. [6] The snout and premaxilla are also smoother than that of most crocodyliforms, without foramina or the typical rugose texture. There are six valid species within this genus, all with slightly differing maxillary or dentary structure. A. gomesii, A. wegeneri and A. tsangatsangana all have a mild concavity of the external alveolar margin of the premaxilla as viewed from the ventral surface; A. rattoides may also have this feature, although this part of its skull is not known, as the dentary suggests that this would be the case. A. rattoides also had the distinctive feature of a highly enlarged and forward-pointing first dentary tooth referred to as an incisiform, resembling the elongated incisors found in rodents (hence the specific epithet). [5]

All species of Araripesuchus had relatively large orbits and hence eyes. They also had thin osteoderms that covered the entire body, multiple rows of them across the back and paired dorsal ones along the tail. Each side of the tail also had a single row of osteoderms, and there were paired ventral osteoderms across most of the belly and underside as well. The osteoderms were not strongly keeled, which, along with the long limb bones and shoulder, hip and ankle joints that suggest upright posture, indicate that Araripesuchus was probably more active on land than on water. [5]

Discovery and history

Block containing multiple specimens of A. wegeneri Araripesuchus fossils.jpg
Block containing multiple specimens of A. wegeneri

The name of the genus was coined in 1959 with the description of the type species Araripesuchus gomesii, a notosuchian crocodylian from the famed Santana Group of the Araripe Basin in Brazil. The holotype used to describe the genus, 423-R is currently in the care of the Divisão de Mineralogia e Geologia do Departamento Nacional da Produção Mineral in Rio de Janeiro. 423-R consists of a single skull articulating with part of a lower jaw. A more complete specimen, AMNH 24450 is held by the American Museum of Natural History. [3] A second species, A. wegeneri was described in 1981. This species was discovered from Early Cretaceous deposits of Niger on the African continent, as opposed to the South American paleodistribution of the other species in the genus. The type specimen for the species, GDF-700 consisting of a few, fragmentary jaw elements, reside at the Museum National d'Histoire Naturelle in Paris. [1] The holotype's fragmentary nature meant that its placement in the genus was disputed until more remains were found in 2009 by Sereno and Larsson; these, along with the specimens of A. tsangatsangana, confirmed its place.

Araripesuchus patagonicus was described from a patagonian specimen (MUC-PV 269) in 2000. [7] Another species to be assigned to the genus, was Araripesuchus buitreraensis , described in 2005. This species was described from a single skull (MPCA-PV 235) retrieved from Late Cretaceous deposits in what is now Argentina. At 130 millimeters, the skull is the largest Araripesuchus specimen discovered to date. [6] A fifth species, Araripesuchus tsangatsangana was described in 2006. This species' type specimen was discovered from latest Late Cretaceous deposits from the African island of Madagascar. Analysis of this specimen solidifies the position of A. wegneri as a member of the genus. A. tsangatsangana is the geologically youngest known of this genus. [2] The sixth species, A. rattoides, was found in the Kem Kem Beds of the Sahara in a similar location to the specimens of A. wegeneri found by Sereno and Larsson, and is known only from parts of dentary bones, up to the fourteenth alveolus. It was described in the same paper as Kaprosuchus , Laganosuchus and Anatosuchus ; the four were therefore popularized by the authors as 'RatCroc', 'BoarCroc', 'PancakeCroc' and 'DuckCroc' respectively. [5]

Classification

Restoration of an adult A. wegeneri Araripesuchus wegeneri.jpg
Restoration of an adult A. wegeneri

There are currently six recognized species within the genus Araripesuchus: A. patagonicus, [7] A. buitreraensis, [6] A. tsangatsangana, [2] A. wegeneri, [1] A. rattoides [5] and the type species A. gomesii. [3] The placement of the first African species discovered, A. wegeneri was questioned for a while by various authors. Ortega et al. argued for the assignment of the errant species to another genus based on phylogenetic analysis [7] Further analysis, combined with the discovery of the second African species A. tsangatsangana has shed more light on the placement of A. wegeneri within the genus. When analyzed together, the African species support the inclusion of all five first described species into the same genus. [2]

The genus was originally assigned by Price to the family Uruguaysuchidae in the original 1959 description. This classification was followed by Buffetaut in 1981 with the description of A. wegeneri also within the same family. [1] However, in their 2000 description of A. patagonicus, Ortega et al. avoided placing the species within the family. Instead, it was simply noted that Uruguaysuchus was a possible close relative of the genus. [7]

Ortega et al. and several other studies place Araripesuchus outside Notosuchia. In some phylogenetic analyses, it is placed closer to the clade Neosuchia, which includes modern crocodilians. In most recent analyses, however, Araripesuchus is placed as a basal notosuchian. The phylogenetic analysis of Soto et al. (2011) joined Araripesuchus with Uruguaysuchus, reinstating the family Uruguaysuchidae. This family was found to be the most basal group of Notosuchia. [8] Below is a cladogram from the analysis:

Holotype right dentary of A. rattoides Araripesuchus rattoides.jpg
Holotype right dentary of A. rattoides
Notosuchia

However, a 2020 study focusing on A. buitreraensis performed phylogenetic analyses which placed A. wegeneri closer to Anatosuchus , while the species from South America are paraphyletic leading to Uruguaysuchus. A. tsangatsangana has been recovered as the most basal species of the family Uruguaysuchidae. This suggests that the monophyly for this genus is rejected, and that Araripesuchus is actually an unnatural grouping of uruguaysuchids. Lumping all species into one genus would lead to Uruguaysuchus taking priority, rendering Araripesuchus a junior synonym of Uruguaysuchus. [9]

Paleoecology

Artist's impression of A. patagonicus Araripesuchus patagonicus SEND.jpg
Artist's impression of A. patagonicus

Araripesuchus remains have been recovered from the continents of South America and Africa suggesting a Gondwanan origin for the evolution of the genus. [1] At around the time of Araripesuchus' existence, South America and Africa were physically adjacent to each other. The various species evolved from the same stock in the general area, radiating outward from a yet-unidentified origin point. The presence of specimens from Madagascar further strengthens this evolutionary radiation model. [2]

Related Research Articles

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

Sarcosuchus is an extinct genus of crocodyliform and distant relative of living crocodilians that lived during the Early Cretaceous, from the late Hauterivian to the late Cenomanian, 133 to 93 million years ago of what are now North Africa and South America. The genus name comes from the Greek σάρξ (sarx) meaning flesh and σοῦχος (souchus) meaning crocodile. It was one of the largest pseudosuchians, with the largest specimen of S. imperator reaching approximately 9–9.5 metres (29.5–31.2 ft) long and weighing up to 3.45–4.3 metric tons. It is known from two species; S. imperator from the early Albian Elrhaz Formation of Niger, and S. hartti from the Late Hauterivian of northeastern Brazil. Other material is known from Morocco and Tunisia and possibly Libya and Mali.

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

Simosuchus is an extinct genus of notosuchian crocodyliforms from the Late Cretaceous of Madagascar. It is named for its unusually short skull. Fully grown individuals were about 0.75 metres (2.5 ft) in length. The type species is Simosuchus clarki, found from the Maevarano Formation in Mahajanga Province, although one isolated multicuspid tooth of this genus was discovered in Kallamedu Formation of India.

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

Anatosuchus is an extinct genus of notosuchian crocodylomorph discovered in Gadoufaoua, Niger, and described by a team of palaeontologists led by the American Paul Sereno in 2003, in the Journal of Vertebrate Paleontology. Its duck-like snout coincidentally makes it resemble a crocoduck, an imagined hybrid animal with the head of a crocodile and the body of a duck.

<i>Razanandrongobe</i> Genus of fossil reptiles related to crocodilians

Razanandrongobe is a genus of carnivorous ziphosuchian crocodyliform from the Middle Jurassic of Madagascar. It contains the type and only species Razanandrongobe sakalavae, named in 2004 by Simone Maganuco and colleagues based on isolated bones found in 2003. The remains, which included a fragment of maxilla and teeth, originated from the Bathonian-aged Sakaraha Formation of Mahajanga, Madagascar. While they clearly belonged to a member of the Archosauria, Maganuco and colleagues refrained from assigning the genus to a specific group because the fragmentary remains resembled lineages among both the theropod dinosaurs and crocodylomorphs.

<span class="mw-page-title-main">Notosuchia</span> Extinct suborder of reptiles

Notosuchia is a suborder of primarily Gondwanan mesoeucrocodylian crocodylomorphs that lived during the Jurassic and Cretaceous. Some phylogenies recover Sebecosuchia as a clade within Notosuchia, others as a sister group ; if Sebecosuchia is included within Notosuchia its existence is pushed into the Middle Miocene, about 11 million years ago. Fossils have been found from South America, Africa, Asia, and Europe. Notosuchia was a clade of terrestrial crocodilians that evolved a range of feeding behaviours, including herbivory (Chimaerasuchus), omnivory (Simosuchus), and terrestrial hypercarnivory (Baurusuchus). It included many members with highly derived traits unusual for crocodylomorphs, including mammal-like teeth, flexible bands of shield-like body armor similar to those of armadillos (Armadillosuchus), and possibly fleshy cheeks and pig-like snouts (Notosuchus). The suborder was first named in 1971 by Zulma Gasparini and has since undergone many phylogenetic revisions.

<span class="mw-page-title-main">Peirosauridae</span> Extinct family of reptiles

Peirosauridae is a Gondwanan family of mesoeucrocodylians that lived during the Cretaceous period. It was a clade of terrestrial crocodyliforms that evolved a rather dog-like skull, and were terrestrial carnivores. It was phylogenetically defined in 2004 as the most recent common ancestor of Peirosaurus and Lomasuchinae and all of its descendants. Lomasuchinae is a subfamily of peirosaurids that includes the genus Lomasuchus.

<span class="mw-page-title-main">Baurusuchidae</span> Extinct family of reptiles

Baurusuchidae is a Gondwanan family of mesoeucrocodylians that lived during the Late Cretaceous. It is a group of terrestrial hypercarnivorous crocodilians from South America and possibly Pakistan. Baurusuchidae has been, in accordance with the PhyloCode, officially defined as the least inclusive clade containing Cynodontosuchus rothi, Pissarrachampsa sera, and Baurusuchus pachecoi. Baurusuchids have been placed in the suborder Baurusuchia, and two subfamilies have been proposed: Baurusuchinae and Pissarrachampsinae.

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

Sphagesaurus is an extinct genus of sphagesaurid notosuchian crocodylomorph from the Late Cretaceous of southwest São Paulo, southern Brazil.

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

Armadillosuchus is an extinct genus of sphagesaurid crocodylomorph. It was described in February 2009 from the late Campanian to early Maastrichtian Adamantina Formation of the Bauru Basin in Brazil, dating to approximately 70 Ma. Armadillosuchus was among the larger and more robust sphagesaurids, with a total length of approximately 2 metres (6.6 ft).

Stolokrosuchus is an extinct genus of crocodyliforms that lived during the Early Cretaceous. Its fossils, including a skull with a long thin snout and bony knobs on the prefrontal, have been found in Niger. Stolokrosuchus was described in 2000 by Hans Larsson and Boubacar Gado. The type species is S. lapparenti. They initially described it as related to Peirosauridae, if not a member of that family. One study has shown it to be related to Elosuchus. However, more recent works usually find Stolokrosuchus to be one of the basalmost neosuchian, only distantly related to the elosuchid or pholidosaurid, Elosuchus. It was a semiaquatic crocodylomorph.

<span class="mw-page-title-main">Metasuchia</span> Clade of reptiles

Metasuchia is a major clade within the superorder Crocodylomorpha. It is split into two main groups, Notosuchia and Neosuchia. Notosuchia is an extinct group that contains primarily small-bodied Cretaceous taxa with heterodont dentition. Neosuchia includes the extant crocodylians and basal taxa, such as peirosaurids and pholidosaurids. It is phylogenetically defined by Sereno et al. (2001) as a clade containing Notosuchus terrestris, Crocodylus niloticus, and all descendants of their common ancestor.

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

Sebecus is an extinct genus of sebecid crocodylomorph from Eocene of South America. Like other sebecosuchians, it was entirely terrestrial and carnivorous. The genus is currently represented by two species, the type S. icaeorhinus and S. ayrampu. Several other species have been referred to Sebecus, but were later reclassified as their own genera.

<span class="mw-page-title-main">Comahuesuchidae</span> Extinct family of reptiles

Comahuesuchidae is a family of notosuchian crocodyliforms. Constructed in 1991, it includes the genera Comahuesuchus and Anatosuchus. Among the characteristics that are unique to this family is an external naris that is inset into the tip of the snout. There is also a diastema, or gap between the teeth, at the tip of the upper and lower jaws. Both Anatosuchus and Comahuesuchus have maxillary tooth rows in the upper jaw that extend out and over the dentary tooth rows of the lower jaw.

Sebecosuchia is an extinct group of mesoeucrocodylian crocodyliforms that includes the families Sebecidae and Baurusuchidae. The group was long thought to have first appeared in the Late Cretaceous with the baurusuchids and become extinct in the Miocene with the last sebecids, but Razanandrongobe pushes the origin of Sebecosuchia to the Middle Jurassic. Fossils have been found primarily from South America but have also been found in Europe, North Africa, Madagascar, and the Indian subcontinent.

<span class="mw-page-title-main">Ziphosuchia</span> Extinct clade of reptiles

Ziphosuchia is a clade of mesoeucrocodylian crocodyliforms that includes notosuchians and sebecosuchians.

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

Caipirasuchus is an extinct genus of sphagesaurid notosuchians known from the Late Cretaceous of northern São Paulo State, southeastern Brazil. The type species, C. paulistanus, was named in 2011. A second species, C. montealtensis, was referred to Caipirasuchus in 2013 after having been named in 2008 as a species of Sphagesaurus. A third species, C. stenognathus, was described in 2014. A fourth species, C. mineirus, was described in 2018. A fifth species, C. attenboroughi, was named in 2021 in honour of David Attenborough.

Labidiosuchus is an extinct genus of notosuchian crocodyliforms from Minas Gerais State, southeastern Brazil. Labidiosuchus had a very bizarre dentition and its lower jaw had a Y-shaped outline.

<span class="mw-page-title-main">Uruguaysuchidae</span> Extinct family of reptiles

Uruguaysuchidae is a family of notosuchian crocodyliforms that lived in South America and Africa during the Cretaceous period. It includes the genera Araripesuchus and Uruguaysuchus. Below is a cladogram from Soto et al. (2011):

<i>Antaeusuchus</i> Genus of extinct animals

Antaeusuchus taouzensis is a species of peirosaurid notosuchian from the Late Cretaceous Kem Kem Group of Morocco. It was described in 2021, and it is the only species in the genus Antaeusuchus. It is the fourth notosuchian described from the region and the second Kem Kem peirosaurid after Hamadasuchus. A 2023 study proposes that Antaeusuchus may not be distinct enough to warrant its own genus and that it instead represents another species of Hamadasuchus.

Barrosasuchus is a genus of peirosaurid notosuchian from the Santonian of Argentina and part of the extensive peirosaurid record of Late Cretaceous Patagonia. It contains one species, Barrosasuchus neuquenianus. B. neuquenianus is known from an almost complete skull and the majority of the articulated postcranial skeleton, making it the best preserved Patagonian peirosaurid.

References

  1. 1 2 3 4 5 Buffetaut, E. (1981). "Die biogeographische Geschichte der Krokodilier, mit Beschreibung einer neuen Art, Araripesuchus wegeneri". Geologische Rundschau. 70 (2): 611–624. Bibcode:1981GeoRu..70..611B. doi:10.1007/BF01822139. S2CID   128870434.
  2. 1 2 3 4 5 Turner, A. H. (2006). "Osteology and phylogeny of a new species of Araripesuchus (Crocodyliformes: Mesoeucrocodylia) from the Late Cretaceous of Madagascar". Historical Biology. 18 (3): 255–369. Bibcode:2006HBio...18..255T. doi:10.1080/08912960500516112. S2CID   83717721.
  3. 1 2 3 Price, L. I. (1959). "Sobre um crocodilideo notossuquio do Cretacico Brasileiro". Boletim Divisao de Geolgia e Mineralogia Rio de Janeiro. 118: 1–55.
  4. Fernández Dumont, M.L.; Bona, P.; Pol, D.; Apesteguía, S. (2020). "New anatomical information on Araripesuchus buitreraensis with implications for the systematics of Uruguaysuchidae (Crocodyliforms, Notosuchia)". Cretaceous Research. 113: 104494. Bibcode:2020CrRes.11304494F. doi:10.1016/j.cretres.2020.104494. S2CID   218942443.
  5. 1 2 3 4 5 Sereno, P.C. & Larsson, H.C.E. (2009). "Cretaceous Crocodyliforms from the Sahara". ZooKeys (28): 1–143. Bibcode:2009ZooK...28....1S. doi: 10.3897/zookeys.28.325 . Archived from the original on 2011-01-09. Retrieved 2009-11-19.
  6. 1 2 3 Pol, Diego & Sebastian Apesteguia (October 2005). "New Araripesuchus remains from the Early Late Cretaceous (Cenomanian–Turonian) of Patagonia". American Museum Novitates (3490): 1. doi:10.1206/0003-0082(2005)490[0001:NARFTE]2.0.CO;2. hdl:2246/5659. ISSN   0003-0082. S2CID   55663842 . Retrieved 2008-12-27.
  7. 1 2 3 4 Ortega, F. J.; Z. B. Gasparini; A. D. Buscalioni & J. O. Calvo (2000). "A new species of Araripesuchus (Crocodylomorpha, Mesoeucrocodylia) from the Lower Cretaceous of Patagonia (Argentina)". Journal of Vertebrate Paleontology. 20 (1): 57–76. doi:10.1671/0272-4634(2000)020[0057:ANSOAC]2.0.CO;2. S2CID   85946263.
  8. Soto, M.; Pol, D. & Perea, D. (2011). "A new specimen of Uruguaysuchus aznarezi (Crocodyliformes: Notosuchia) from the middle Cretaceous of Uruguay and its phylogenetic relationships". Zoological Journal of the Linnean Society. 163 (S1): S173–S198. doi: 10.1111/j.1096-3642.2011.00717.x . hdl: 11336/69086 .
  9. Fernandez dumont, M.L.; Bona, P.; Pol, D.; Apesteguía, S. (2020). "New anatomical information on Araripesuchus buitreraensis with implications for the systematics of Uruguaysuchidae (Crocodyliforms, Notosuchia)". Cretaceous Research. 113. 104494. Bibcode:2020CrRes.11304494F. doi:10.1016/j.cretres.2020.104494. S2CID   218942443.