Allodaposuchus

Last updated

Contents

Allodaposuchus
Temporal range: Campanian-Maastrichtian
~84.9–66.043  Ma
Allodaposuchus precedens.jpg
A. precedens skull
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: Eusuchia
Clade: Allodaposuchidae
Genus: Allodaposuchus
Nopcsa, 1928
Type species
Allodaposuchus precedens
Nopcsa, 1928
Species
  • A. precedensNopcsa, 1928
  • A. subjuniperus? Puértolas et al., 2013 (also Agaresuchus)
  • A. palustrisBlanco et al., 2014
  • A. hulkiBlanco et al., 2015
  • A. iberoarmoricanusBlanco, 2021
  • A. fontisensis? (Narváez et al., 2016; originally Agaresuchus)
  • A. megadontos? (Narváez et al. 2015; originally Lohuecosuchus)
  • A. mechinorum? (Narváez et al. 2015; originally Lohuecosuchus)
Synonyms

Allodaposuchus is an extinct genus of crocodyliforms that lived in what is now southern Europe during the Campanian and Maastrichtian stages of the Late Cretaceous. Although generally classified as a non-crocodylian eusuchian crocodylomorph, it is sometimes placed as one of the earliest true crocodylians. Allodaposuchus is one of the most common Late Cretaceous crocodylomorphs from Europe, with fossils known from Romania, Spain, and France.

Description

Restoration of A. precedens Allodaposuchus BW.jpg
Restoration of A. precedens

Like many other Cretaceous crocodylomorphs, Allodaposuchus has a relatively small body size compared to living crocodylians. The largest known specimen of Allodaposuchus belongs to an individual that was probably around 3 metres (9.8 ft) long. [1] Although the shape varies between species, in general Allodaposuchus has a short, flattened, and rounded skull. Allodaposuchus precedens has a brevirostrine or "short-snouted" skull with a snout about the same length as the skull table (the region of the skull behind the eye sockets) and A. subjuniperus has a mesorostrine or "middle-snouted" skull with a snout that is longer than the skull table. [1] [2] The main feature that distinguishes Allodaposuchus species from other related crocodylomorphs is the orientation of a groove at the back of the skull called the cranioquadrate passage; unlike the cranioquadrate passages of other crocodylomorphs, which are only visible at the back of the skull, the cranioquadrate passage of Allodaposuchus is visible when the skull is viewed from the side. [3]

At least one species of Allodaposuchus, A. hulki, may have adaptations that would have allowed it to live on land for extended periods of time. A. hulki has large sinuses in its skull that are not seen in any other crocodylian living or extinct and may have aided it in hearing out of water, as well as lightening the skull. Moreover, A. hulki has well-developed muscle attachments on its scapula, humerus, and ulna bones that would have allowed the forelimbs to have been held in a semi-erect stance suitable for walking over land. Remains of A. hulki come from interbedded sandstones and marls that, based on the presence of charophyte algae, likely formed in ephemeral ponds in a large floodplain far from permanent bodies of water like lakes or rivers. A. hulki may therefore have spent much of its time out of water, travelling between these ponds for food. [4]

History of study

While there are several described species of Allodaposuchus, the precise membership of the group is currently disputed.

Allodaposuchus precedens

The type species of Allodaposuchus, A. precedens, was named by Hungarian paleontologist Franz Nopcsa in 1928 from Vălioara, Romania. [5] Nopcsa found bone fragments in a deposit of the Hațeg Basin that dates back to the late Maastrichtian stage – the very end of the Late Cretaceous. Several partial skulls from Spain and France were attributed to A. precedens in 2001. [6] Some of these skulls came from Campanian-age deposits slightly older than those in Romania, meaning that the species must have persisted for about 5 million years. [1]

A 2013 study proposed that the French and Spanish fossils assigned to A. precedens in 2001 might actually represent a new unnamed species of Allodaposuchus currently identified as Allodaposuchus sp. [1] A study published in 2005 had suggested that these fossils belong to several different genera of crocodylomorphs and that the original Romanian material is too fragmentary to assign to its own genus, making Allodaposuchus a nomen dubium or "dubious name". [7] However, the 2013 study reaffirmed the Romanian material's distinctiveness from other European Cretaceous crocodylomorphs and therefore reaffirmed the validity of Allodaposuchus as a genus. [1]

Allodaposuchus (Agaresuchus) subjuniperus ?

In 2013, a second species of Allodaposuchus, A. subjuniperus, was named on the basis of a skull from the late-Maastrichtian Conquès Formation, part of the Tremp Group, in the province of Huesca, Spain. The skull was found underneath a juniper tree whose roots had grown between the bones, hence the species name subjuniperus or "under juniper" in Latin. [1] However, in 2016, A. subjuniperus was moved to a new genus, Agaresuchus along with the type species of that genus, A. fontisensis, on the grounds that the Spanish species were sufficiently distinct from A. precedens. [8] In 2021, a phylogenetic analysis by Blanco disputed this result, suggesting that both A. fontisensis and A. subjuniperus belong within the genus Allodaposuchus proper, alongside the two species of Lohuecosuchus : L. megadontos and L. mechinorum. [9]

Allodaposuchus palustris

In 2014, A. palustris was described from a partial skull and other skeletal fragments found in Maastrichtian age sediments of the Tremp Formation in a fossil locality called Fumanya Sud in the southern Pyrenees. [10] These remains allowed for the first detailed description of the postcranial (non-skull) anatomy of Allodaposuchus.

Allodaposuchus hulki

A fourth species of Allodaposuchus, A. hulki, was named in 2015 and also came from the Tremp Formation, although this time in a locality called Casa Fabà. The species is named after the Hulk from Marvel Comics, in reference to features on the bones that suggest it had strong muscles. [4]

Allodaposuchus iberoarmoricanus

A. palustris was described by Blanco in 2021 based on fossils discovered in Late Campanian-aged fluvial deposits in Velaux-La Bastide Neuve, in Bouches-du-Rhône Department of southern France. [9] The species name is in reference to the Ibero-Armorican island of the Cretaceous European Archipelago. [9]

Allodaposuchus (Agaresuchus) fontisensis ?

In 2016, the new genus and species Agaresuchus fontisensis was discovered and described. It was named from the Lo Hueco fossil site in Fuentes, Cuenca, Spain; fontis is the Latin name of Fuentes. [8] A. subjuniperus was then also placed into the new genus Agaresuchus. [8] However, Blanco's 2021 study has called this into question, and instead proposed that they should both be considered members of Allodaposuchus, with Agaresuchus as a junior synonym. [9]

Allodaposuchus (Lohuecosuchus) megadontos and Allodaposuchus (Lohuecosuchus) mechinorum ?

The genus Lohuecosuchus was named in 2015 and contained two species, L. megadontos and L. mechinorum, from Spain and southern France. [11] However, Blanco's 2021 study has called this into question, and instead proposed that they should both be considered members of Allodaposuchus, with Lohuecosuchus as a junior synonym. [9]

Classification

jaw fragments and teeth of A. palustris Allodaposuchus palustris.png
jaw fragments and teeth of A. palustris
Skeletal diagram showing known remains of A. palustris Allodaposuchus palustris skeletal diagram.png
Skeletal diagram showing known remains of A. palustris

Allodaposuchus belongs to the clade Allodaposuchidae. The exact placement of Allodaposuchidae is still in dispute. Narváez et al. considered it the sister group to Hylaeochampsidae, which together form a clade that is sister to Crocodylia. [11] Other studies have alternatively recovered them not as sister taxon, but rather as an evolutionary grade towards Crocodylia, with Hylaeochampsidae more basal than Allodaposuchidae. [12] [13] Alternatively, a 2021 analysis incorporating postcranial information recovered Allodaposuchidae within Crocodylia. [14]

The internal phylogeny of Allodaposuchidae can be shown in the cladogram below from the 2021 Blanco study: [14]

Allodaposuchidae

Arenysuchus gascabadiolorum

Allodaposuchus precedens

Allodaposuchus iberoarmoricanus

Allodaposuchus subjuniperus

Allodaposuchus palustris

Allodaposuchus hulki

In the 2021 study, Blanco recovered Allodaposuchus as paraphyletic, with Agaresuchus and Lohuecosuchus . Accordingly, Blanco proposed that Agaresuchus and Lohuecosuchus should be considered junior synonyms of Allodaposuchus. [14]

Related Research Articles

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

Boverisuchus is an extinct genus of planocraniid crocodyliforms known from the middle Eocene of Germany and western North America. It was a relatively small crocodyliform with an estimated total length of approximately 2.2–3.6 metres (7.2–11.8 ft).

Pachycheilosuchus is an extinct genus of neosuchian from the Early Cretaceous of Texas, United States. Previously known, in part, as the "Glen Rose form", this crocodylomorph is notable for its procoelous vertebrae, otherwise found only in derived eusuchian crocodilians, a thick margin on the maxillae, and a shield of armor on the neck formed by the fusion of six individual scutes.

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

Borealosuchus is an extinct genus of crocodyliforms that lived from the Late Cretaceous to the Eocene in North America. It was named by Christopher Brochu in 1997 for several species that had been assigned to Leidyosuchus. The species assigned to it are: B. sternbergii, the type species, from the Maastrichtian of Colorado, Montana, North Dakota, South Dakota, and Wyoming; B. acutidentatus, from the Paleocene of Saskatchewan; B. formidabilis, from the Paleocene of North Dakota; B. griffithi, from the Paleocene of Alberta; and B. wilsoni, from the Eocene of Wyoming. B. formidabilis is particularly well-known, represented by the remains of many individuals from the Wannagan Creek site in North Dakota.

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

Eusuchia is a clade of neosuchian crocodylomorphs that first appeared in the Early Cretaceous, which includes modern crocodilians. Along with Dyrosauridae and Sebecosuchia, they were the only crocodyliformes who survived the K-Pg extinction.

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

Acynodon is an extinct genus of eusuchian crocodylomorph from the Late Cretaceous, with fossils found throughout Southern Europe.

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

Massaliasuchus is an extinct monospecific genus of allodaposuchid eusuchian crocodyliform that is known from fossils found in Santonian–Campanian-age Upper Cretaceous rocks of southeastern France.

Dolichochampsa is an extinct genus of eusuchian crocodylomorph. It is the type genus and only member of the family Dolichochampsidae. Fossils have been found in the Yacoraite Formation of Argentina and the El Molino Formation of Bolivia of Maastrichtian age. It had a distinctive slender snout. Because the material associated with the specimens is so fragmentary, its relationships with other eusuchians remain unknown. Jouve et al. (2020) assigned Dolichochampsa to Gavialoidea, making it the oldest known South American member of this clade.

<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.

Hylaeochampsa is an extinct genus of eusuchian crocodylomorphs. It is known only from a partial skull recovered from Barremian-age rocks of the Lower Cretaceous Vectis Formation of the Isle of Wight. This skull, BMNH R 177, is short and wide, with a eusuchian-like palate and inferred enlarged posterior teeth that would have been suitable for crushing. Hylaochampsa was described by Richard Owen in 1874, with H. vectiana as the type species. It may be the same genus as the slightly older Heterosuchus, inferred to have been of similar evolutionary grade, but there is no overlapping material as Heterosuchus is known only from vertebrae. If the two could be shown to be synonyms, Hylaeochampsa would have priority because it is the older name. Hylaeochampsa is the type genus of the family Hylaeochampsidae, which also includes Iharkutosuchus from the Late Cretaceous of Hungary. James Clark and Mark Norell positioned it as the sister group to Crocodylia. Hylaeochampsa is currently the oldest known unambiguous eusuchian.

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

Thoracosaurus is an extinct genus of long-snouted eusuchian which existed during the Late Cretaceous and Early Paleocene in North America and Europe.

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

Musturzabalsuchus is an extinct monospecific genus of allodaposuchid eusuchian crocodyliform. The type and only species is Musturzabalsuchus buffetauti.

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

Ischyrochampsa is an extinct monospecific genus of Late Cretaceous crocodyliform belonging to the eusuchian clade Allodaposuchidae. Fossils of the type species I. meridionalis are late Campanian in age and were found in the commune of Saint-Estève-Janson in Bouches-du-Rhône, France. Material is also known from Spain. It was named and described in 1995, and it had an estimated length of over 4 metres (13 ft).

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

Arenysuchus is an extinct monospecific genus of allodaposuchid eusuchian crocodylomorph from Late Cretaceous deposits of north Spain. It is known from the holotype MPZ ELI-1, a partial skull from Elías site, and from the referred material MPZ2010/948, MPZ2010/949, MPZ2010/950 and MPZ2010/951, four teeth from Blasi 2 site. It was found by the researchers José Manuel Gasca and Ainara Badiola from the Tremp Formation, in Arén of Huesca, Spain. It was first named by Eduardo Puértolas, José I. Canudo and Penélope Cruzado-Caballero in 2011 and the type species is Arenysuchus gascabadiolorum.

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

Planocraniidae is an extinct family of eusuchian crocodyliforms known from the Paleogene of Asia, Europe and North America. The family was coined by Li in 1976, and contains three genera, Boverisuchus, Duerosuchus and Planocrania. Planocraniids were highly specialized crocodyliforms that were adapted to living on land. They had extensive body armor, long legs, and blunt claws resembling hooves, and are sometimes informally called "hoofed crocodiles".

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


Allodaposuchidae is an extinct clade of eusuchians that lived in Europe during the Late Cretaceous (Santonian-Maastrichtian).

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

Lohuecosuchus is an extinct genus of allodaposuchid eusuchian crocodylomorph that lived during the Late Cretaceous in what is now Spain and southern France.

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

Agaresuchus is an extinct genus of allodaposuchid eusuchian crocodylomorph from the Late Cretaceous (Campanian-Maastrichtian) of Spain. It includes two species, the type species Agaresuchus fontisensis, and Agaresuchus subjuniperus, which was originally named as a species of the related genus Allodaposuchus. However, it has been proposed that both species may instead belong to the genus Allodaposuchus.

Portugalosuchus is an extinct genus of eusuchian crocodyliform that was possibly a basal crocodylian – if so then it would be the oldest known crocodylian to date. The type species is P. azenhae, described in 2018, and it is known from the Late Cretaceous (Cenomanian)-aged Tentugal Formation in Portugal. A 2021 morphological study recovered Portugalosuchus within Crocodylia as a member of Gavialidae closely related to similar "thoracosaurs", while also noting that it might also possibly be outside of Crocodylia completely. A 2022 tip dating analysis incorporating both morphological and DNA data placed Portugalosuchus outside of Crocodylia, as the sister taxon of the family Allodaposuchidae. A cladogram simplified after that analysis is shown below:

Aprosuchus is a genus of small-bodied Maastrichtian atoposaurid Eusuchian from the Hateg Basin, Romania.

Titanochampsa is a genus of large mesoeucrocodylian from the Maastrichtian Marilia Formation of Brazil. Although only known from a single skull roof, the material shows that Titanochampsa was not a member of Notosuchia, which were previously believed to have been the only crocodyliforms present in the strata of the Bauru Group. Body size estimates vary greatly and range between 2.98–5.88 m due to the incomplete nature of the holotype fossil. The overall anatomy of the skull roof, alongside its size and possible affinities with Neosuchians, may suggest that it was a semi-aquatic ambush hunter similar to modern crocodilians.

References

  1. 1 2 3 4 5 6 Puértolas-Pascual, E.; Canudo, J.I.; Moreno-Azanza, M. (2014). "The eusuchian crocodylomorph Allodaposuchus subjuniperus sp. nov., a new species from the latest Cretaceous (upper Maastrichtian) of Spain". Historical Biology. 26 (1): 91–109. doi:10.1080/08912963.2012.763034. S2CID   85004774.
  2. Martin, J.E. (2010). "Allodaposuchus Nopsca, 1928 (Crocodylia, Eusuchia), from the Late Cretaceous of southern France and its relationships to Alligatoroidea". Journal of Vertebrate Paleontology . 30: 756–767. doi:10.1080/02724631003758318.
  3. Delfino, M.; Codrea, V.; Folie, A.; Dica, P.; Godefroit, P.; Smith, T. (2008). "A complete skull of Allodaposuchus precedens Nopcsa, 1928 (Eusuchia) and a reassessment of the morphology of the taxon based on the Romanian remains". Journal of Vertebrate Paleontology . 28: 111–122. doi:10.1671/0272-4634(2008)28[111:ACSOAP]2.0.CO;2.
  4. 1 2 Blanco, Alejandro; Fortuny, Josep; Vicente, Alba; Luján, Angel H.; García Marçà, Jordi Alexis; Sellés, Albert G. (2015). "A new species of Allodaposuchus (Eusuchia, Crocodylia) from the Maastrichtian (Late Cretaceous) of Spain: phylogenetic and paleobiological implications". PeerJ . 3:e1171: 1–35. doi: 10.7717/peerj.1171 . PMC   4558081 . PMID   26339549.
  5. Nopcsa, F (1928). "Paleontological notes on Reptilia. 7. Classification of the Crocodilia". Geologica Hungarica, Series Palaeontologica. 1: 75–84.
  6. Buscalioni, A.D.; Ortega, F.; Weishampel, D.B.; Jianu, C.M. (2001). "A revision of the crocodyliform Allodaposuchus precedens from the Upper Cretaceous of the Hateg Basin, Romania. Its relevance in the phylogeny of Eusuchia". Journal of Vertebrate Paleontology . 21: 74–86. doi:10.1671/0272-4634(2001)021[0074:AROTCA]2.0.CO;2.
  7. Martin, J.E.; Buffetaut, E. (2005). "An overview of the Late Cretaceous crocodilian assemblage from Cruzy, southern France". Kaupia. 14: 33–40.
  8. 1 2 3 Narváez, I.; Brochu, C.A.; Escaso, F.; Pérez-García, A.; Ortega, F. (2016). "New Spanish Late Cretaceous eusuchian reveals the synchronic and sympatric presence of two allodaposuchids". Cretaceous Research. 65: 112–125. doi: 10.1016/j.cretres.2016.04.018 .
  9. 1 2 3 4 5 Blanco, A. (2021). "Importance of the postcranial skeleton in eusuchian phylogeny: Reassessing the systematics of allodaposuchid crocodylians". PLOS ONE. 16 (6): e0251900. Bibcode:2021PLoSO..1651900B. doi: 10.1371/journal.pone.0251900 . PMC   8189472 . PMID   34106925.
  10. Blanco, Alejandro; Puértolas Pascual, Eduardo; Marmi, Josep; Vila, Bernat; Sellés, Albert G. (2014). "Allodaposuchus palustris sp. nov. from the Upper Cretaceous of Fumanya (South Eastern Pyrenees, Iberian Peninsula): Systematics, Palaeoecology and Palaeobiogeography of the Enigmatic Allodaposuchian Crocodylians". PLoS One . 9: 1–34. doi: 10.1371/journal.pone.0115837 . PMC   4281157 .
  11. 1 2 Narváez, I.; Brochu, C.A.; Escaso, F.; Pérez-García, A.; Ortega, F. (2015). "New crocodyliforms from southwestern Europe and definition of a diverse clade of european Late Cretaceous basal eusuchians". PLOS ONE. 10 (11): e0140679. Bibcode:2015PLoSO..1040679N. doi: 10.1371/journal.pone.0140679 . PMC   4633049 . PMID   26535893.
  12. 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.
  13. 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.
  14. 1 2 3 Blanco, Alejandro (2021-06-09). "Importance of the postcranial skeleton in eusuchian phylogeny: Reassessing the systematics of allodaposuchid crocodylians". PLOS ONE . 16 (6): e0251900. Bibcode:2021PLoSO..1651900B. doi: 10.1371/journal.pone.0251900 . ISSN   1932-6203. PMC   8189472 . PMID   34106925.