Isalorhynchus

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Isalorhynchus
Temporal range: Carnian
Isalorhynchus FMNH.jpg
Skeleton of Isalorhynchus genovefae in the Field Museum of Natural History.
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Clade: Archosauromorpha
Order: Rhynchosauria
Family: Rhynchosauridae
Subfamily: Hyperodapedontinae
Genus: Isalorhynchus
Buffetaut, 1983
Species
  • I. genovefae Buffetaut, 1983 (type)
Synonyms

Isalorhynchus is an extinct genus of hyperodapedontine rhynchosaur from the late Triassic period (Carnian stage) of Toliara Province, southwestern Madagascar. It is known from the holotype MDE-R18, a nearly complete maxilla and from other specimens from the same locality, Malio River area. It was found in the Makay Formation (or Isalo II) of the Morondava Basin (or Isalo beds). It was first named by Eric Buffetaut in 1983 and the type species is Isalorhynchus genovefae. [1] The majority of Isalorhynchus specimens are isolated jaw bones, but two nearly complete skeletons were found in 1998. [2] Langer et al., 2000 concluded that Isalorhynchus is a synonym of Hyperodapedon and referred it to a new species of Hyperodapedon. [3] Whatley, 2005 retained this genus as valid with a description of new materials in her PhD thesis. [4] Montefeltro et al., 2010 and Langer et al., 2010 accepted Isalorhynchus as valid genus. [5] [6]

Phylogeny

Isalorhynchus in a cladogram based on Ezcurra et al. (2016): [7]

Rhynchosauria

Noteosuchus

Mesosuchus

Howesia

Eohyosaurus

Rhynchosauridae

Rhynchosaurus

Stenaulorhynchinae

Mariante rhynchosaur

Stenaulorhynchus

Langeronyx

Bentonyx

Fodonyx

Hyperodapedontinae

Isalorhynchus

Teyumbaita

Hyperodapedon

Related Research Articles

<span class="mw-page-title-main">Archosauromorpha</span> Infraclass of reptiles

Archosauromorpha is a clade of diapsid reptiles containing all reptiles more closely related to archosaurs rather than lepidosaurs. Archosauromorphs first appeared during the late Middle Permian or Late Permian, though they became much more common and diverse during the Triassic period.

<span class="mw-page-title-main">Rhynchosaur</span> Extinct order of reptiles

Rhynchosaurs are a group of extinct herbivorous Triassic archosauromorph reptiles, belonging to the order Rhynchosauria. Members of the group are distinguished by their triangular skulls and elongated, beak like premaxillary bones. Rhynchosaurs first appeared in the Early Triassic, reaching their broadest abundance and a global distribution during the Carnian stage of the Late Triassic.

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

Hyperodapedon is an extinct genus of rhynchosaur reptiles which lived during Late Triassic period. Like other rhynchosaurs, it was an heavily built archosauromorph, distantly related to archosaurs such as crocodilians and dinosaurs. Hyperodapedon in particular was part of the subfamily Hyperodapedontinae, a specialized rhynchosaurian subgroup with broad skulls, beaked snouts, and crushing tooth plates on the roof of the mouth.

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

Rhynchosaurus is a genus of rhynchosaur that lived during the Middle Triassic period. It lived in Europe. It was related to the archosaurs, but not within that group. The type species of Rhynchosaurus is R. articeps. Michael Benton named two additional species, R. spenceri and R. brodiei, but they were subsequently renamed Fodonyx and Langeronyx respectively. Fossils of Rhynchosaurus have been found in the Tarporley Siltstone Formation and possibly the Sherwood Sandstone Group of the United Kingdom.

The Tiki Formation is a Late Triassic geologic formation in Madhya Pradesh, northern India. Dinosaur remains are among the fossils that have been recovered from the formation, although none have yet been referred to a specific genus. Phytosaur remains attributable to the genus Volcanosuchus have also been found in the Tiki Formation.

Paleontology or palaeontology is the study of prehistoric life forms on Earth through the examination of plant and animal fossils. This includes the study of body fossils, tracks (ichnites), burrows, cast-off parts, fossilised feces (coprolites), palynomorphs and chemical residues. Because humans have encountered fossils for millennia, paleontology has a long history both before and after becoming formalized as a science. This article records significant discoveries and events related to paleontology that occurred or were published in the year 2010.

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

Bentonyx is an extinct genus of rhynchosaur from the middle Triassic epoch of Devon in England. Its fossil, a well preserved skull, BRSUG 27200, was discovered in Otter Sandstone Formation and was first assigned to Rhynchosaurus spenceri, that is known from 25 specimens. This species was reassigned to its own genus, Fodonyx, that was first described by David W. E. Hone and Michael Benton in 2008. More recently, this skull was reassigned to this genus by Max C. Langer, Felipe C. Montefeltro, David E. Hone, Robin Whatley and Cesar L. Schultz in 2010 and the type species is Bentonyx sidensis.

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

Fodonyx is an extinct genus of rhynchosaur from the middle Triassic epoch of Devon in England. Its fossils were discovered in Otter Sandstone Formation and were first assigned to Rhynchosaurus spenceri. This species was reassigned to its own genus, Fodonyx the holotype of which is EXEMS 60/1985/292, that described by David W. E. Hone and Michael J. Benton in 2008. In 2010, one skull was reassigned to the new genus Bentonyx. It is distinguished from other rhynchosaurs by a single autapomorphy, the ventral angling of the paraoccipital processes. In all other rhynchosaurs these processes angle dorsally or are horizontal. It is not known if this conferred any advantage to Fodonyx. Fodonyx was between 40 and 50 cm long.

Teyumbaita is an extinct genus of hyperodapedontine rhynchosaur from the Upper Triassic of southern Brazil. Its fossils were recovered from the early Norian-age Caturrita Formation, one of several fossiliferous formations exposed at Paleorrota Geopark in the state of Rio Grande do Sul. Teyumbaita is likely the youngest valid genus of rhynchosaur, as other members of the group likely died out before the start of the Norian.

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

Stenaulorhynchus is an extinct genus of hyperodapedontid rhynchosaur known from the Middle Triassic deposits of Tanganyika Territory, Tanzania. It was found in the Lifua Member of the Manda Formation in the Karoo Supergroup. It was named and first described by Sidney Henry Haughton in 1932. The type species is Stenaulorhynchus stockleyi, a beaked herbivore measuring 1–6 meters in length.

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

Howesia is an extinct genus of basal rhynchosaur from early Middle Triassic deposits of Eastern Cape, South Africa. It is known from the holotype SAM 5884, a partial skeleton with palate and partial lower jaws and from two paratypes, SAM 5885 and SAM 5886. It was found in the Burgersdorp Formation of the middle deposits of the Beaufort Group and referred to Subzone B of the Cynognathus Assemblage Zone. It was first named by Robert Broom in 1905 and the type species is Howesia browni, named after Alfred Brown.

Supradapedon is an extinct genus of hyperodapedontine rhynchosaur from mid-late Triassic deposits of Tanganyika Territory, Tanzania. It is known from the holotype SAM-11704. The holotype and only specimen of Supradapedon was first assigned to a species of Scaphonyx, Scaphonyx stockleyi. This species was reassigned to its own genus by Sankar Chatterjee in 1980 and the type species is Supradapedon stockleyi. One study, Langer et al. (2000), concluded that Supradapedon is a synonym of Hyperodapedon and referred it to Hyperodapedon sp. However, the provisional validity of this genus has been commonly accepted since.

<span class="mw-page-title-main">Hyperodapedontinae</span> Extinct subfamily of reptiles

Hyperodapedontinae is a subfamily of rhynchosaurs within the family Rhynchosauridae. Fossils have been found from Argentina, Brazil, Canada, India, Madagascar, Scotland, Tanzania, United States and Zimbabwe.

Macrocephalosaurus is a genus of rhynchosaurs from the Late Triassic period of southern Brazil. It contains a single species, Macrocephalosaurus mariensis. Although usually synonymized with Hyperodapedon, some cladistic analyses have called this synonymy into question.

Otischalkia is an extinct genus of archosauromoph from late Triassic deposits of Howard County, Texas, US It is known from the holotype TMM 31025-263, left humerus and from the referred specimens TMM 31025-262, TMM 31025-266, TMM 31025-264, TMM 31185-92 and TMM 31185-93. It was found in the Lower Dockum Group near the abandoned settlement of Otis Chalk. It was first named by Adrian P. Hunt and Spencer G. Lucas in 1991 and the type species is Otischalkia elderae.

<span class="mw-page-title-main">Epipophyses</span> Bony projections of neck vertebrae in certain reptiles

Epipophyses are bony projections of the cervical vertebrae found in archosauromorphs, particularly dinosaurs. These paired processes sit above the postzygapophyses on the rear of the vertebral neural arch. Their morphology is variable and ranges from small, simple, hill-like elevations to large, complex, winglike projections. Epipophyses provided large attachment areas for several neck muscles; large epipophyses are therefore indicative of a strong neck musculature.

Langeronyx is an extinct genus of basal rhynchosaurid known from the early Middle Triassic Bromsgrove Sandstone Formation of Warwickshire, UK. It contains a single species, Langeronyx brodiei, originally included in the genus Rhynchosaurus. R. brodiei was first described and named by Michael Benton in 1990, but its redescription by Martín D. Ezcurra, Felipe Montefeltro and Richard J. Butler in 2016 recovered it as more closely related to the more advance hyperodapedontine than to the type species of Rhynchosaurus and thus it was moved to its own genus. The generic name Langeronyx honors the Brazilian paleontologist Max Cardoso Langer in recognition of his rhynchosaur research, combined with the Greek onyx (óνυξ) meaning "claw", a common suffix for rhynchosaur genera. L. brodiei is known solely from the holotype, a partial skull divided into the two specimens WARMS G6097/1 and NHMUK PV R8495, housed in the Warwickshire Museum, Warwick and Natural History Museum, London, respectively. Other specimens originally referred to R. brodiei either do not overlap with its type or can be just as likely referred to other basal rhynchosaurids. L. brodiei is one of two basal archosauromorphs known from the Bromsgrove Sandstone Formation, the other being the lesser known Rhombopholis scutulata.

Isalo II, also known as the Makay Formation, is an informal Triassic geological unit in Madagascar.

Oryctorhynchus is an extinct genus of rhynchosaur from the Late Triassic (Carnian-Norian)-aged Wolfville Formation of Nova Scotia, Canada that may have been the same animal as Beesiiwo. The type species, O. bairdi, was named and described in 2020. It was originally seen as a species of Hyperodapedon until 2020.

<i>Beesiiwo</i> Genus of hyperodapedontine rhynchosaur from the Late Triassic

Beesiiwo is a genus of hyperodapedontine rhynchosaur from the Late Triassic Popo Agie Formation in Western Wyoming. The type and only species is B. cooowuse, known from four specimens consisting of left and right maxilla fragments, and a left dentary fragment.

References

  1. Eric Buffetaut (1983). "Isalorhynchus genovefae, n. g. n. sp. (Reptilia, Rhyncocephalia), um nouveau Rhyncosaure du Trias de Madagascar". Annales de Paléontologie. 1983: 465–480.
  2. Whatley, R.L.; Flynn, J.J.; Parrish, J.M.; Simpson, W.; Wyss, A.R. (1999). "Isalorhynchus revisited: two rhynchosaur skeletons from southwestern Madagascar". Journal of Vertebrate Paleontology. 19 (3 Suppl): 84A. doi:10.1080/02724634.1999.10011202.
  3. M. Langer; M. Boniface; G. Cuny; L. Barbieri (2000). "The phylogenetic position of Isalorhynchus genovefae, a Late Triassic rhynchosaur from Madagascar". Annales de Paléontologie. 86 (2): 101–127. Bibcode:2000AnPal..86..101L. doi:10.1016/s0753-3969(00)80002-6.
  4. Whatley, R. L. (2005). Phylogenetic relationship of Isalorhynchus genovefae, the rhynchosaur (Reptilia, Archosauromorpha) from Madagascar (PhD Thesis). University of California, Santa Barbara. 276 pp.
  5. Felipe Chinaglia Montefeltro; Max Cardoso Langer; Cesar Leandro Schultz (2010). "Cranial anatomy of a new genus of hyperodapedontine rhynchosaur (Diapsida, Archosauromorpha) from the Upper Triassic of southern Brazil". Earth and Environmental Science Transactions of the Royal Society of Edinburgh. 101 (1): 27–52. Bibcode:2010EESTR.101...27M. doi:10.1017/S1755691010009060. S2CID   129472459.
  6. Max C. Langer; Felipe C. Montefeltro; David E. Hone; Robin Whatley; Cesar L. Schultz (2010). "On Fodonyx spenceri and a new rhynchosaur from the Middle Triassic of Devon". Journal of Vertebrate Paleontology. 30 (6): 1884–1888. Bibcode:2010JVPal..30.1884L. doi:10.1080/02724634.2010.521901. S2CID   53405231.
  7. Martin D. Ezcurra; Felipe C. Montefeltro; Richard J. Butler (2016). "The Early Evolution of Rhynchosaurs" (PDF). Frontiers in Ecology and Evolution. 3: 1–24. doi: 10.3389/fevo.2015.00142 . Archived (PDF) from the original on 2024-02-20.