Pholidosaurus Temporal range: Early Cretaceous, | |
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Pholidosaurus meyeri skull fossil at the Museum für Naturkunde, Berlin | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Reptilia |
Clade: | Pseudosuchia |
Superorder: | Crocodylomorpha |
Family: | † Pholidosauridae |
Genus: | † Pholidosaurus Meyer, 1841 |
Species | |
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Synonyms | |
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Pholidosaurus is an extinct genus of neosuchian crocodylomorph. It is the type genus of the family Pholidosauridae. Fossils have been found in northwestern Germany. The genus is known to have existed during the Berriasian-Albian stages of the Early Cretaceous. Fossil material found from the Annero and Jydegård Formations in Skåne, Sweden and on the island of Bornholm, Denmark, have been referred to as a mesoeucrocodylian, and possibly represent the genus Pholidosaurus. [1]
An early description of the genus by Lydekker (1888) mentioned that the orbit is slightly smaller than the supratemporal fossa, the nasals reach the premaxillae, and the vomer appears on the palate. [2] It is similar in appearance to and about as large as the modern gharial.
The type species of Pholidosaurus is P. schaumburgensis, named in 1841 from the Wealden of Bückeburg, Germany. [2] [3] P. schaumburgensis was named on the basis of a natural mould of part of a thorax discovered in around 1830 from the Berriasian Obernkirchen Sandstein. [4] This mould is known as IMGPGö 741-1. The individual that the mould belonged to is thought to have been around 25 centimetres (9.8 in) in length. [5]
Macrorhynchus is a junior synonym of Pholidosaurus. [6] It was named in 1843 from the same stratigraphic unit and region as P. schaumbergensis, with the type species being M. meyeri. [7] Because M. meyeri bears a strong resemblance to Pholidosaurus schaumburgensis, it is now regarded as a species of Pholidosaurus. It was reassigned to the genus Pholidosaurus in 1887 by Richard Lydekker because of this synonymy, and also because the name Macrorhynchus was preoccupied by a genus of fish named in 1880. [3] P. meyeri differs from P. schaumburgensis in that the bar separating the supratemporal fenestrae is rounded, while in the type species it is rounded. [2]
Pholidosaurus decipiens was erected for a partial cranium, NHMUK 28432, that was originally assigned to the new genus and species Petrosuchus laevidens by Richard Owen in 1878. [8] Petrosuchus laevidens was based on this cranium and a mandibular ramus called BMNH 41099, both of which were collected from Swanage, England. A later study in 1911 concluded that the material belonged to two different species; NHMUK 28432 was reassigned to Pholidosaurus and NHMUK 41099 was designated the lectotype of Petrosuchus laevidens. The species name decipiens was coined in reference to Owen's oversight, and Petrosuchus is now considered a junior synonym of Goniopholis simus . [5]
Another species from England, P. purbeckensis, was originally described as a species of Steneosaurus in 1888. [9] The holotype is an almost complete cranium, referred to as DORCM G97, missing the anterior portion of the rostrum. The skull was found from either Swanage or the Isle of Purbeck (hence the species name), although the exact locality from which the skull originated is not specified by the author of the original description. [10] This material was also once referred to Macrorhynchus. The author of the 1888 description considered S. purbeckensis an intermediate form between Steneosaurus and Teleosaurus . [9] However, in 2002, a new study showed that S. purbeckensis was conspecific with P. decipiens, creating the new combination Pholidosaurus purbeckensis. [5]
Another species of Pholidosaurus, P. laevis, was named in 1913 from Swanage, based on the partial cranium NHMUK R3414. [11] This has been considered a junior synonym of P. purbeckensis by both Salisbury et al. (1999) and Salisbury (2002). [5] [12]
In an SVPCA abstract, Smith et al. (2016) noted that Pholidosaurus purbeckensis is not congeneric with the type species, and instead is closely related to Fortignathus and members of Dyrosauridae. [13]
Phylogenetic position of Pholidosaurus | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Richard Lydekker assigned Pholidosaurus to the family Goniopholididae in 1887 along with Hylaeochampsa , Theriosuchus , Goniopholis , and Petrosuchus because the vertebrae are amphicoelus and the orbit communicates with the lateral temporal fossa. [3]
Pholidosaurus has often been grouped with other longirostrine, or long-snouted, crocodylomorphs, including dyrosaurids and thalattosuchians. Buckley and Brochu (1999) concluded that Pholidosaurus, Sokotosuchus , Dyrosauridae, and Thalattosuchia formed a longirostrine clade that was the sister taxon to Crocodylia. [16] However, Thalattosuchia was traditionally considered a more basal clade of crocodylomorphs, being a more basal lineage of Mesoeucrocodylia than dyrosaurids or Pholidosaurus, both of which were considered neosuchians. [17] The results of the phylogenetic analysis by Buckley and Brochu (1999) were attributed to the similarity in characters associated with snout elongation seen in these crocodylomorphs, even though these characters may have been independently derived in each group. More recent studies have revealed Thalattosuchia as a more basal clade when dyrosaurids are removed from the data set. [18]
More recent studies show that Pholidosaurus is closely related to the Thalattosuchia, with both taxa closely related to a clade containing Terminonaris and the Dyrosauridae. [19] In a phylogenetic analysis conducted by Sereno et al. (2001), Pholidosaurus was placed as a distant sister taxon to the other longirostrine crocodylomorphs, with Terminonaris and the newly named Sarcosuchus being closely related to one another and Dyrosaurus being the next closest taxon to the group. [14] The later phylogenetic analysis of Brochu et al. (2002) again showed that Pholidosaurus was closely related to Thalattosuchia. In the study, both taxa formed a clade that was the sister taxon to a clade containing Sokotosuchus and Dyrosauridae. [20] Jouve et al. (2006) concluded that Pholidosaurus was closely related thalattosuchians were also included within the family, which would be considered paraphyletic without them. Jouve et al. (2006), like Buckley and Brochu (1999), attributed this result to phylogenetic problems that exist among longirostrine crocodylomorphs due to similarities in their morphology. [21]
Echinodon is a genus of heterodontosaurid dinosaur that lived during the earliest Cretaceous of southern England and possibly western France in the Berriasian epoch. The first specimens were jaw bones named Echinodon becklesii by Sir Richard Owen in 1861, and since their original description only additional teeth have been discovered. The specific name honours collector Samuel Beckles who discovered the material of Echinodon and many other taxa from across England, while the genus name translates as "prickly tooth" in reference to the dental anatomy of the taxon.
Goniopholis is an extinct genus of goniopholidid crocodyliform that lived in Europe and Africa during the Late Jurassic and Early Cretaceous. Being semi-aquatic it is very similar to modern crocodiles. It ranged from 2–4 metres in length, and would have had a very similar lifestyle to the American alligator or Nile crocodile.
Metriorhynchus is an extinct genus of marine crocodyliform that lived in the oceans during the Late Jurassic. The type species, M. brevirostris was named in 1829 as a species of Steneosaurus before being named as a separate genus by the German palaeontologist Christian von Meyer in 1832. The name Metriorhynchus means "Moderate snout", and is derived from the Greek Metrio- ("moderate") and -rhynchos ("snout").
Purranisaurus is an extinct genus of marine crocodyliform from the Middle to Late Jurassic period of Chile and Vaca Muerta of Argentina. Rusconi originally regarded Purranisaurus potens to be a plesiosaur; however, Gasparini demonstrated that it was in fact a metriorhynchid crocodyliform, and that may be a junior synonym of Metriorhynchus. It was about 3–3.3 m (9.8–10.8 ft) long and weighed 80 kg (180 lb).
Dyrosauridae is a family of extinct neosuchian crocodyliforms that lived from the Late Cretaceous (Maastrichtian) to the Eocene. Dyrosaurid fossils are globally distributed, having been found in Africa, Asia, Europe, North America and South America. Over a dozen species are currently known, varying greatly in overall size and cranial shape. A majority were aquatic, some terrestrial and others fully marine, with species inhabiting both freshwater and marine environments. Ocean-dwelling dyrosaurids were among the few marine reptiles to survive the Cretaceous–Paleogene extinction event.
Elosuchus is an extinct genus of neosuchian crocodyliform that lived during the Middle Cretaceous of what is now Africa.
Hyposaurus is a genus of extinct marine dyrosaurid crocodyliform. Fossils have been found in Paleocene aged rocks of the Iullemmeden Basin in West Africa, Campanian–Maastrichtian Shendi Formation of Sudan and Maastrichtian through Danian strata in New Jersey, Alabama and South Carolina. Isolated teeth comparable to Hyposaurus have also been found in Thanetian strata of Virginia. It was related to Dyrosaurus. The priority of the species H. rogersii has been debated, however there is no sound basis for the recognition of more than one species from North America. The other North American species are therefore considered nomina vanum.
Pholidosauridae is an extinct family of aquatic neosuchian mesoeucrocodylian crocodylomorphs. Fossils have been found in Europe, Africa, North America and South America. The pholidosaurids first appeared in the fossil record during the Bathonian stage of the Middle Jurassic. Jouve & Jalil (2020) described postcranial material of a pholidosaurid from the Paleocene (Danian) of Ouled Abdoun Basin (Morocco), representing the most recent record of the family. The authors also reinterpreted putative Maastrichtian dyrosaurid Sabinosuchus as a pholidosaurid, and argued that at least two independent pholidosaurid lineages reached the Maastrichtian, among which one survived the Cretaceous–Paleogene extinction event. Before the publication of this study it was thought that the family became extinct during the Late Turonian stage of the Late Cretaceous.
Neosuchia is a clade within Mesoeucrocodylia that includes all modern extant crocodilians and their closest fossil relatives. It is defined as the most inclusive clade containing all crocodylomorphs more closely related to Crocodylus niloticus than to Notosuchus terrestris. Members of Neosuchia generally share a crocodilian-like bodyform adapted to freshwater aquatic life, as opposed to the terrestrial habits of more basal crocodylomorph groups. The earliest neosuchian is suggested to be the Early Jurassic Calsoyasuchus, which lived during the Sinemurian and Pliensbachian stages in North America. It is often identified as a member of Goniopholididae, though this is disputed, and the taxon may lie outside Neosuchia, which places the earliest records of the group in the Middle Jurassic.
Phosphatosaurus is an extinct genus of dyrosaurid crocodylomorph. It existed during the early Eocene, with fossils having been found from North Africa in Tunisia and Mali. Named in 1955, Phosphatosaurus is a monotypic genus; the type species is P. gavialoides. A specimen has been discovered from Niger, but it cannot be classified at the species level.
Rhabdognathus is an extinct genus of dyrosaurid crocodylomorph. It is known from rocks dating to the Paleocene epoch from western Africa, and specimens dating back to the Maastrichtian era were identified in 2008. It was named by Swinton in 1930 for a lower jaw fragment from Nigeria. The type species is Rhabdognathus rarus. Stéphane Jouve subsequently assessed R. rarus as indeterminate at the species level, but not at the genus level, and thus dubious. Two skulls which were assigned to the genus Rhabdognathus but which could not be shown to be identical to R. rarus were given new species: R. aslerensis and R. keiniensis, both from Mali. The genus formerly contained the species Rhabdognathus compressus, which was reassigned to Congosaurus compressus after analysis of the lower jaw of a specimen found that it was more similar to that of the species Congosaurus bequaerti. Rhabdognathus is believed to be the closest relative to the extinct Atlantosuchus.
Theriosuchus is an extinct genus of atoposaurid neosuchian from Late Jurassic to Early Cretaceous of Europe, Southeast Asia (Thailand) and western North America (Wyoming), with fragmentary records from Middle Jurassic and Early Cretaceous sites in China, Morocco, and Scotland.
Shantungosuchus is an extinct genus of Early Cretaceous crocodyliform found in China. It includes three species: Shantungosuchus chuhsienensis and S. brachycephalus, which were both described by Yang Zhongjian – usually referred to as "Young" – in 1961 and 1982, and S. hangjinensis, which was described by Xiao-Chun Wu et al in 1994. S. chuhsienensis is the type for this genus.
Acherontisuchus is an extinct genus of dyrosaurid neosuchian from Middle to Late Paleocene deposits of Colombia. The only known species is A. guajiraensis, whose name means "Acheron crocodile of the Guajira Peninsula".
Tethysuchia is an extinct clade of neosuchian mesoeucrocodylian crocodylomorphs from the late Middle Jurassic to the Early Eocene of Asia, Europe, North America and South America. It was named by the French paleontologist Eric Buffetaut in 1982 as a suborder. Tethysuchia was considered to be a synonym of Dyrosauridae or Pholidosauridae for many years. In most phylogenetic analyses the node Dyrosauridae+Pholidosauridae was strongly supported. De Andrade et al. (2011) suggested that Tethysuchia be resurrected for that node. They defined it as a node-based taxon "composed of Pholidosaurus purbeckensis and Dyrosaurus phosphaticus, their common ancestor and all its descendants". In their analysis they found that the support for Tethysuchia is actually stronger than the support for Thalattosuchia. The following cladogram shows the position of Tethysuchia among the Neosuchia sensu this study.
Bathysuchus is an extinct genus of teleosaurid thalattosuchian from Late Jurassic (Kimmeridgian) deep water marine deposits in England and France. Bathysuchus displays features that suggest it was more pelagic than other teleosaurids, including smoother skull bones and reduced armour plating, similar to the fully marine metriorhynchids. This was possibly an adaptation to rising sea levels during the Kimmeridgian, as its earlier relatives such as Teleosaurus were suited for shallow coasts and lagoon environments.
Anthracosuchus is an extinct genus of dyrosaurid crocodyliform from the Paleocene of Colombia. Remains of Anthracosuchus balrogus, the only known species, come from the Cerrejón Formation in the Cerrejón mine, and include four fossil specimens with partial skulls. Anthracosuchus differs from other dyrosaurids in having an extremely short (brevirostrine) snout, widely spaced eye sockets with bony protuberances around them, and osteoderms that are smooth and thick. It is one of the most basal dyrosaurids along with Chenanisuchus and Cerrejonisuchus.
Coelognathosuchia is an extinct clade of neosuchian crocodyliforms that includes all taxa more closely related to the family Pholidosauridae than to Bernissartia fagesii or Eusuchia. Martin et al. (2014) named the clade after finding goniopholidids and pholidosaurids to group together in their phylogenetic analysis of crocodyliform evolutionary relationships. In their analysis, Pholidosauridae was monophyletic and Goniopholididae was paraphyletic, being an assemblage of successively more basal taxa within Coelognathosuchia. Coelognathosuchia itself was positioned near the base of the larger clade Neosuchia as the sister group to a clade containing the Early Cretaceous neosuchian Bernissartia and Eusuchia, the group that includes all modern crocodilians and their closest extinct relatives.
Roxochampsa is an extinct genus of crocodylomorph from the Late Cretaceous of Brazil belonging to the sebecosuchian clade Itasuchidae. The type species is R. paulistanus.
Fortignathus is an extinct genus of dyrosaurid or peirosaurid crocodylomorph known from the Late Cretaceous Echkar Formation in Niger. It contains a single species, Fortignathus felixi, which was originally named as a species of Elosuchus in 2002.
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