Alierasaurus

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Alierasaurus
Temporal range: early Middle Permian [1] Roadian
Alierasaurus reconstruction.jpg
Reconstruction of Alierasaurus by Emiliano Troco.
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Synapsida
Clade:† Caseasauria
Family:† Caseidae
Genus:† Alierasaurus
Romano and Nicosia, 2014
Species:
†A. ronchii
Binomial name
†Alierasaurus ronchii
Romano and Nicosia, 2014

Alierasaurus is an extinct genus of caseid synapsid that lived during the early Middle Permian (Roadian) [1] in what is now Sardinia. [2] It is represented by a single species, the type species Alierasaurus ronchii. Known from a very large partial skeleton found within the Cala del Vino Formation, Alierasaurus is one of the largest known caseids. It closely resembles Cotylorhynchus , another giant caseid from the San Angelo Formation in Texas. The dimensions of the preserved foot elements and caudal vertebrae suggest an estimated total length of about 6 or 7 m (20 or 23 ft) for Alierasaurus. [3] [4] [5] In fact, the only anatomical features that differ between Alierasaurus and Cotylorhynchus are found in the bones of the feet; Alierasaurus has a longer and thinner fourth metatarsal and it has ungual bones at the tips of the toes that are pointed and claw-like rather than flattened as in other caseids. Alierasaurus and Cotylorhynchus both have very wide, barrel-shaped rib cages indicating that they were herbivores that fed primarily on high-fiber plant material. [3]

Contents

Etymology

Ungual phalanx (which supported a horny claw) of Alierasaurus ronchii in dorsal and right lateral views. Alierasaurus ronchii claw.jpg
Ungual phalanx (which supported a horny claw) of Alierasaurus ronchii in dorsal and right lateral views.

The generic name refers to Aliera, the name in local dialect of the town of Alghero, and ‘saurus’ meaning lizard. The specific name is in honor of Ausonio Ronchi the discoverer of the specimen. [3]

Description

The paleontologists Marco Romano and Umberto Nicosia have identified several autapomorphies in the feet anatomy of Alierasaurus: metatarsal IV with distinct axial region, length about twice that of the corresponding proximal phalanx, not short and massive as in other large caseids; metatarsal IV proximal head not orthogonal to the bone axis, forming an angle of 120° with the shaft: with this conformation, the proximal and distal heads are much closer along the medial side of the metatarsal; claw-shaped ungual phalanges proportionally shorter than in Cotylorhynchus, with a double ventral flexor tubercle very close to the proximal rim of the phalanx; ungual phalangeal axis bent downward and medially; distal transverse section subtriangular, not spatulate as in Cotylorhynchus. [3]

Discovery

The Torre del Porticciolo promontory, where the remains of Alierasaurus were discovered. Torre del porticiolo242 o.jpg
The Torre del Porticciolo promontory, where the remains of Alierasaurus were discovered.
Caudal vertebra of Alierasaurus ronchii in lateral, anterior and posterior views. Alierasaurus caudal vertebra.jpg
Caudal vertebra of Alierasaurus ronchii in lateral, anterior and posterior views.

The holotype of Alierasaurus was discovered in the uppermost levels of the Permian Cala del Vino Formation, on top of the Torre del Porticciolo promontory, which separates the Porticciolo Gulf from the northern coast (near the town of Alghero, Nurra, northwest Sardinia). [2] Some bones were found loose on the ground surface, and others still embedded in mudstone-siltstone layer. These sediments were deposited in a former alluvial plain under a relatively mild semi-arid climate. [2] The known material consist of eight articulated caudal vertebrae, two isolated caudal vertebrae, four distal caudal centra, numerous large fragments referable to at least eight other vertebrae, seven proximal portions of hemal arches, three proximal portions (vertebral segment) of dorsal ribs, ten undetermined fragmentary ribs, poorly preserved right scapula and badly crushed right coracoid plate, distal head of the left ulna, and several autopodial elements represented by a fragmentary calcaneum, three metapodials, five non-ungual phalanges, an almost complete ungual phalanx, and two ungual phalanges lacking distal ends. [3] These remains were firstly regarded as belonging possibly to Cotylorhynchus (cf Cotylorhynchus sp. in the publication of Ronchi et al.) or to a closely related taxon. Later, despite the absence of the most diagnostic elements (notably the skull) for the comparison with other caseids in general and with Cotylorhynchus in peculiar, the Sardinian specimen was assigned to a new genus named Alierasaurus, on the basis of some differences in feet anatomy. [2] [3] In 2017, Marco Romano and colleagues described other bones belonging to the same individual (some caudal vertebrae and fragments of chevrons and ribs). [4] More recently, the same levels have yielded remains of an undescribed sphenacodontid pelycosaur, and footprints of a third animal which was only known in the south of France in slightly younger rocks (ichnogenus Merifontichnus from the La Lieude Formation (Wordian) in the Lodève basin). [5] [1]

Taphonomy

Articulated caudal vertebrae of Alierasaurus ronchii in situ. Alierasaurus caudal vertebrae.jpg
Articulated caudal vertebrae of Alierasaurus ronchii in situ.

Remains of Alierasaurus were discovered grouped together on an area of a few square meters. Some lay on the ground, exposed by erosion, while others were still in the sediment. Most of the bones were isolated except for two foot bones and 8 caudal vertebrae found articulated. The bones still in place in the rock were not all on the same bedding plane but were buried at different depths within a 40 cm thick red siltstone layer. Several bones were fractured before burial. The taphonomy of the site indicates a complex burial process in several phases. Shortly after the death of the animal, the carcass was transported from the death place to a second burial place. This short transport was violent enough to break some bones. Subsequently, the corpse, still on the surface of the sediments, underwent a further rather short phase of decomposition before a new flash flood packed all the remains into a large amount of fine-grained sediment, transported them, and finally deposits them all together in a third place close to the previous one. This third phase of deposition explains why the bones are found at different depths in the sedimentary layer. [2]

Paleogeography

Distribution of caseid synapsids in late Paleozoic Pangea.jpg
Distribution of caseid synapsids in late Paleozoic Pangea detail.jpg
Left: paleogeographic map of Earth at the end of the Paleozoic showing the known distribution of caseid synapsids. Right: close-up of the paleogeographic location of the caseid sites. 1 and 2 Ennatosaurus tecton , Arkhangelsk Oblast, Russia, late Roadian – early Wordian ; 3 Phreatophasma aenigmaticum , Bashkortostan, Russia, early Roadian ; 4 Datheosaurus macrourus Lower Silesian Voivodeship, Poland, Gzhelian ; 5 Martensius bromackerensis , Thuringia, Germany, Sakmarian ; 6 Callibrachion gaudryi , Saône-et-Loire, France, Asselian ; 7 Euromycter rutenus and Ruthenosaurus russellorum , Aveyron, France, late Artinskian ; 8 Lalieudorhynchus gandi , Hérault, France, Wordian – early Capitanian ; 9Alierasaurus ronchii, Nurra, Sardinia, Italy, Roadian ; 10 Eocasea martini , Greenwood County, Kansas, late Pennsylvanian ; 11 Angelosaurus romeri and Cotylorhynchus bransoni , Kingfisher County, Oklahoma, early Roadian ; 12 Cotylorhynchus bransoni , Blaine County, Oklahoma, early Roadian ; 13 Cotylorhynchus romeri , Logan County, Oklahoma, mid-late Kungurian ; 14 Cotylorhynchus romeri , Cleveland County, Oklahoma, mid-late Kungurian ; 15 Oromycter dolesorum and Arisierpeton simplex , Comanche County, Oklahoma, early Artinskian ; 16 Cotylorhynchus hancocki , Hardeman County, Texas, late Kungurian – early Roadian ; 17 Cotylorhynchus hancocki , Angelosaurus dolani , A. greeni , Caseoides sanangeloensis , and Caseopsis agilis , Knox County, Texas, late Kungurian – early Roadian ; 18 Casea broilii , Baylor County, Texas, mid-late Kungurian.

In Guadalupian time, most of the landmasses were united in one supercontinent, Pangea. It was roughly C-shaped: its northern (Laurasia) and southern (Gondwana) parts were connected to the west, but separated to the east by the very large Tethys Sea. [6] A long string of microcontinents, grouped under the name Cimmeria, divided the Tethys in two : the Paleo-Tethys in the north, and the Neo-Tethys in the south. [7] Sardinia was located in the equatorial belt of the time, at the level of the 10th parallel north. It was not an island at all and was part of Pangea. At that time, Sardinia (and Corsica) was connected to what is now southeastern France. [8] [9] The precise paleoposition of the Sardinia-Corsica block was determined in the early 2000s from detailed lithostratigraphic correlations between the Permian and Triassic successions of the Nurra region in northwestern Sardinia and the Toulon-Cuers Basin in Var department (where the Saint-Mandrier Formation is equivalent to the Cala del Vino Formation). The remarkable lithological similarities of the Nurra region with that of Toulon-Cuers Basin indicate that the two regions were initially closely faced each other and were parts of the same basin. [9] [10] [nb 1] The Sardinia-Corsica block was rotated 60° clockwise from its current orientation. The south of Sardinia was then located near the east of the Pyrenees (whose mountains did not yet exist), and the north-west of Corsica was positioned in front of the Massif de l'Esterel (the rhyolites of the Scandola peninsula aligning with those of the Esterel, of similar age and composition). [9] [11]

Stratigraphic range

No radiometric dating is available for the Cala del Vino formation. Its age estimates range from late Kungurian to early Capitanian. [2] [1] [12] [13] These ages are inferred on the basis of direct and indirect stratigraphic correlations with the Permian basins of Provence (including the Toulon-Cuers basin which constituted a single sedimentary basin with the Nurra region) and coupled with paleontological data from Provence and Occitania. The Cala del Vino Formation is lithostratigraphically correlated with the Saint-Mandrier Formation of the Toulon-Cuers basin. The Saint-Mandrier Formation has not yet yielded any fossils, but it probably dates from the Guadalupian because it locally overlies lacustrine limestones and black mudstones of the Bau Rouge Member of the Les Salettes Formation which have yielded macroflora and microflora, respectively, suggesting a late Kungurian - early Roadian age. The lower part of the Saint-Mandrier Formation is correlated with the Les Pradineaux Formation of the Esterel basin in Provence. This formation overlies, above an unconformity, a rhyolitic formation (the A7 Rhyolite) dated at 272.5 ± 0.3 Ma. [10] [14] This absolute age, formerly considered as late Kungurian, [10] [14] corresponds now to the early Roadian. [12] On the other hand, the Les Pradineaux Formation contains in its lower part the A11 Rhyolite which itself is undated but which is crossed by a fluorite-barite vein with adularia dated at 264 ± 2 Ma corresponding to the Capitanian, indicating an older age for the A11 Rhyolite and the Les Pradineaux Formation. [15] Marc Durand suggests a Wordian age, the erosional gap at the top of the A7 Rhyolite corresponding according to him to a large part of the Roadian. [10] [15] The Les Pradineaux Formation has, however, yielded plants and pollens suggesting a Roadian age, an ostracod fauna indicative of a late Roadian age, and vertebrate tracks including the ichnogenus Brontopus characteristic of the Guadalupian. [10] [16] [17] [12] [18] From these stratigraphic correlations, the Sardinian Cala del Vino Formation could thus be dated to the Roadian - Wordian. According to Werneburg and colleagues the age of the Cala del Vino formation could also extend from the Roadian to the early Capitanian like the La Lieude Formation of the Lodève basin, due to sedimentological similarities and the co-occurrence in the two formations of the caseids synapsids and the ichnogenus Merifontichnus. [13]

Phylogeny

In 2017 Marco Romano and colleagues published the first phylogenetic analysis including the genus Alierasaurus. It is recovered as the sister taxon of the genus Cotylorhynchus . [4]

Below the cladogram published by Romano and colleagues in 2017. [4]

Caseasauria


In describing the genus Martensius in 2020, Berman and colleagues published two cladograms. In the first, the position of caseids more derived than Martensius is poorly resolved. Alierasaurus forms a polytomy with Angelosaurus romeri and the three species of Cotylorhynchus. In the second cladogram, Alierasaurus is positioned above the genus Angelosaurus and forms a polytomy with Cotylorhynchus romeri and a clade containing the species C. bransoni and C. hancocki. [19]

Below the two cladograms published by Berman and colleagues in 2020. [19]

Caseidae


Caseidae


In 2022, Werneburg and colleagues described the genus Lalieudorhynchus and published a phylogenetic analysis which concluded that Angelosaurus and Cotylorhynchus would be paraphyletic, both genera being possibly represented only by their type species. In this analysis, Cotylorhynchus romeri is positioned just above the genus Angelosaurus, and forms a polytomy with a clade containing Ruthenosaurus and Caseopsis and another clade containing Alierasaurus, the other two species of Cotylorhynchus and Lalieudorhynchus. Within the latter clade, Alierasaurus is the sister group of “Cotylorhynchus” bransoni and a more derived clade including Lalieudorhynchus and “Cotylorhynchus” hancocki. [13]

Below is the cladogram published by Werneburg and colleagues in 2022. [13]

Caseidae


Notes

  1. ↑ It was not until the Oligocene that the Sardinia-Corsica block began to separate from what is now southeastern France (Durand, 2008).

Related Research Articles

<span class="mw-page-title-main">Guadalupian</span> Second series and epoch of the Permian

The Guadalupian is the second and middle series/epoch of the Permian. The Guadalupian was preceded by the Cisuralian and followed by the Lopingian. It is named after the Guadalupe Mountains of New Mexico and Texas, and dates between 272.95 ± 0.5 – 259.1 ± 0.4 Mya. The series saw the rise of the therapsids, a minor extinction event called Olson's Extinction and a significant mass extinction called the end-Capitanian extinction event. The Guadalupian was previously known as the Middle Permian.

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

Pareiasaurs are an extinct clade of large, herbivorous parareptiles. Members of the group were armoured with osteoderms which covered large areas of the body. They first appeared in southern Pangea during the Middle Permian, before becoming globally distributed during the Late Permian. Pareiasaurs were the largest reptiles of the Permian, reaching sizes equivalent to those of contemporary therapsids. Pareiasaurs became extinct in the Permian–Triassic extinction event.

In the geologic timescale, the Capitanian is an age or stage of the Permian. It is also the uppermost or latest of three subdivisions of the Guadalupian Epoch or Series. The Capitanian lasted between 264.28 and 259.51 million years ago. It was preceded by the Wordian and followed by the Wuchiapingian.

In the geologic timescale, the Roadian is an age or stage of the Permian. It is the earliest or lower of three subdivisions of the Guadalupian Epoch or Series. The Roadian lasted between 273.01 and 266.9 million years ago (Ma). It was preceded by the Kungurian and followed by the Wordian.

<span class="mw-page-title-main">Caseasauria</span> Extinct clade of synapsids

Caseasauria is one of the two main clades of early synapsids, the other being the Eupelycosauria. Caseasaurs are currently known only from the Late Carboniferous and the Permian, and include two superficially different families, the small insectivorous or carnivorous Eothyrididae, and the large, herbivorous Caseidae. These two groups share a number of specialised features associated with the morphology of the snout and external naris.

<span class="mw-page-title-main">Caseidae</span> Extinct family of vertebrate animals

Caseidae are an extinct family of basal synapsids that lived from the Late Carboniferous to Middle Permian between about 300 and 265 million years ago. Fossils of these animals come from the south-central part of the United States, from various parts of Europe, and possibly from South Africa if the genus Eunotosaurus is indeed a caseid as some authors proposed in 2021. Caseids show great taxonomic and morphological diversity. The most basal taxa were small insectivorous and omnivorous forms that lived mainly in the Upper Carboniferous and Lower Permian, such as Eocasea, Callibrachion, and Martensius. This type of caseid persists until the middle Permian with Phreatophasma and may be Eunotosaurus. During the early Permian, the clade is mainly represented by many species that adopted a herbivorous diet. Some have evolved into gigantic forms that can reach 6–7 metres (20–23 ft) in length, such as Cotylorhynchus hancocki and Alierasaurus ronchii, making them the largest Permian synapsids. Caseids are considered important components of early terrestrial ecosystems in vertebrate history because the numerous herbivorous species in this family are among the first terrestrial tetrapods to occupy the role of primary consumer. The caseids experienced a significant evolutionary radiation at the end of the early Permian, becoming, with the captorhinid eureptiles, the dominant herbivores of terrestrial ecosystems in place of the edaphosaurids and diadectids.

Caseoides is an extinct genus of large caseid synapsids that lived in the Kungurian Age. It was about 3 metres (9.8 ft) long, and like many other caseids, it was herbivorous and aquatic. It weighed between 150 and 200 kilograms. Its fossils were found in San Angelo Formation, Texas. Caseoides was very similar to Casea, but was slightly larger in size. Caseoides was a heavily built creature, as are most of the Caseids. In the development of its proportionally thick, stout limbs it represents the culmination of the Casea lineage. Its relatives became smaller during the Roadian Age. Only poorly preserved postcranial material is known including limbs.

Casea is a genus of herbivorous caseid synapsids that lived during the late Lower Permian (Kungurian) in what is now Texas, United States. The genus is only represented by its type species, Casea broilii, named by Samuel Wendell Williston in 1910. The species is represented by a skull associated with a skeleton, a second skull, a partial skull with a better preserved dentition than that of the preceding skulls, and several incomplete postcranial skeletons. Three other Casea species were later erected, but these are considered today to be invalid or belonging to different genera. Casea was a small animal with a length of about 1.20 m and a weight of around 20 kg.

<i>Cotylorhynchus</i> Extinct genus of synapsids

Cotylorhynchus is an extinct genus of herbivorous caseid synapsids that lived during the late Lower Permian (Kungurian) and possibly the early Middle Permian (Roadian) in what is now Texas and Oklahoma. The large number of specimens found make it the best-known caseid. Like all large herbivorous caseids, Cotylorhynchus had a short snout sloping forward and very large external nares. The head was very small compared to the size of the body. The latter was massive, barrel-shaped, and ended with a long tail. The limbs were short and robust. The hands and feet had short, broad fingers with powerful claws. The barrel-shaped body must have housed large intestines, suggesting that the animal had to feed on a large quantity of plants of low nutritional value. Caseids are generally considered to be terrestrial, though a semi-aquatic lifestyle has been proposed by some authors. The genus Cotylorhynchus is represented by three species, the largest of which could reach more than 6 m in length. However, a study published in 2022 suggests that the genus may be paraphyletic, with two of the three species possibly belonging to separate genera.

Angelosaurus is an extinct genus of herbivorous caseid synapsids that lived during the late Lower Permian (Kungurian) and early Middle Permian (Roadian) in what is now Texas and Oklahoma. Like other herbivorous caseids, it had a small head, large barrel-shaped body, long tail, and massive limbs. Angelosaurus differs from other caseids by the extreme massiveness of its bones, particularly those of the limbs, which show a strong development of ridges, processes, and rugosities for the attachment of muscles and tendons. Relative to its body size, the limbs of Angelosaurus were shorter and wider than those of other caseids. The ungual phalanges looked more like hooves than claws. The few known cranial elements show that the skull was short and more robust than that of the other representatives of the group. Angelosaurus is also distinguished by its bulbous teeth with shorter and wider crowns than those of other caseids. Their morphology and the high rate of wear they exhibit suggests a diet quite different from that of other large herbivorous caseids, and must have been based on particularly tough plants. A study published in 2022 suggests that the genus may be paraphyletic, with Angelosaurus possibly only represented by its type species A. dolani.

<i>Ennatosaurus</i> Extinct genus of synapsids

Ennatosaurus is an extinct genus of caseid synapsid that lived during the Middle Permian in northern European Russia. The genus is only represented by its type species, Ennatosaurus tecton, which was named in 1956 by Ivan Antonovich Efremov. The species is known from at least six skulls associated with their lower jaws, as well as from the postcranial bones of several juvenile individuals. Ennatosaurus has the typical caseid skull with a short snout tilted forward and very large external nares. However, it differs from other derived caseids by its postcranial skeleton with smaller proportions compared to the size of the skull. As with other advanced caseids, the teeth of Ennatosaurus were well suited for slicing and cutting vegetation. The presence of a highly developed hyoid apparatus indicates the presence of a massive and mobile tongue, which had to work in collaboration with the palatal teeth during swallowing. With a late Roadian - early Wordian age, Ennatosaurus is one of the last known caseids.

<i>Phreatophasma</i> Extinct genus of synapsids

Phreatophasma is an extinct genus of synapsids from the Middle Permian of European Russia. It includes only one species, Phreatophasma aenigmatum, which is itself known from a single femur found in a mine near the town of Belebei in Bashkortostan. Phreatophasma comes from a fossil assemblage that is latest Ufimian to earliest Kazanian in age under the Russian stratigraphic scheme, correlating with the Roadian Age under the international stratigraphic timescale. Because the species is based on a single specimen with few diagnostic anatomical features, uncertainty remains as to where it belongs in tetrapod phylogeny; originally interpreted in 1954 as an enigmatic "theromorph" synapsid by Soviet paleontologist Ivan Yefremov, Phreatophasma was later described as a therapsid incertae sedis by American paleontologist Alfred Romer in 1956 and then as a member of a basal synapsid family called Caseidae starting with Everett C. Olson in 1962. Olson's classification was later supported by Canadian paleontologist Robert Reisz in 1986 and American paleontologist Robert L. Carroll in 1988. Ivakhneneko et al. (1997) and Maddin et al. (2008) both considered Phreatophasma an indeterminate synapsid.

<i>Callibrachion</i>

Callibrachion is an extinct genus of caseid synapsids that lived in east-central France during the Lower Permian (Asselian). The holotype and only known specimen (MNHN.F.AUT490) is represented by an almost complete postcranial skeleton associated with skull fragments discovered at the end of the 19th century in the Permian Autun basin in Saône-et-Loire department, in the Bourgogne-Franche-Comté region. It belongs to an immature individual measuring less than 1.50 m in length. Callibrachion was long considered a junior synonym of the genus Haptodus and classified among the sphenacodontid pelycosaurs. In 2015, a new study found that Callibrachion was a different animal from Haptodus and that it was a caseasaur rather than a sphenacodontid. This was confirmed in 2016 by a cladistic analysis which recovered Callibrachion as a basal caseid. Callibrachion's sharp teeth and unenlarged ribcage indicate that this animal was likely faunivorous.

Ruthenosaurus is an extinct genus of caseid synapsids that lived in what is now Southern France during the Early Permian about 285 million years ago. It is known from the holotype MNHN.F.MCL-1 an articulated partial postcranial skeleton. It was collected by D. Sigogneau-Russell and D. Russell in 1970 in the upper part of the M2 Member, Grès Rouge Group, in the Rodez Basin, near the village of Valady, in Occitanie Region. It was first named by Robert R. Reisz, Hillary C. Maddin, Jörg Fröbisch and Jocelyn Falconnet in 2011, and the type species is Ruthenosaurus russellorum.

<i>Euromycter</i> Extinct genus of synapsids

Euromycter is an extinct genus of caseid synapsids that lived in what is now Southern France during the Early Permian about 285 million years ago. The holotype and only known specimen of Euromycter (MNHN.F.MCL-2) includes the complete skull with lower jaws and hyoid apparatus, six cervical vertebrae with proatlas, anterior part of interclavicle, partial right clavicle, right posterior coracoid, distal head of right humerus, left and right radius, left and right ulna, and complete left manus. It was collected by D. Sigogneau-Russell and D. Russell in 1970 at the top of the M1 Member, Grès Rouge Group, near the village of Valady, Rodez Basin. It was first assigned to the species "Casea" rutena by Sigogneau-Russell and Russell in 1974. More recently, it was reassigned to its own genus, Euromycter, by Robert R. Reisz, Hillary C. Maddin, Jörg Fröbisch and Jocelyn Falconnet in 2011. The preserved part of the skeleton suggests a size between 1,70 m (5,5 ft) and 1,80 m (5,9 ft) in length for this individual.

<i>Arisierpeton</i> Extinct genus of synapsids

Arisierpeton is an extinct genus of synapsids from the Early Permian Garber Formation of Richards Spur, Oklahoma. It contains a single species, Arisierpeton simplex.

<i>Cabarzia</i> Extinct genus of lizard-like animals

Cabarzia is an extinct genus of varanopid from the Early Permian of Germany. It contains only a single species, Cabarzia trostheidei, which is based on a well-preserved skeleton found in red beds of the Goldlauter Formation. Cabarzia shared many similarities with Mesenosaurus romeri, although it did retain some differences, such as more curved claws, a wide ulnare, and muscle scars on its sacral ribs. With long, slender hindlimbs, a narrow body, an elongated tail, and short, thick forelimbs, Cabarzia was likely capable of running bipedally to escape from predators, a behavior shared by some modern lizards. It is the oldest animal known to have adaptations for bipedal locomotion, predating Eudibamus, a bipedal bolosaurid parareptile from the slightly younger Tambach Formation.

<i>Paraxenisaurus</i> Genus of deinocheirid dinosaur (fossil)

Paraxenisaurus is an extinct genus of ornithomimosaurian theropod from the Late Cretaceous Cerro del Pueblo Formation of Coahuila in Mexico. The genus contains a single species, P. normalensis, which is known from a few bones of tail, hips, hands, and feet. The specific epithet was given in honor of the Benemérita Normal School of Coahuila, a teacher training institution, where the fossils were reposited. It is a member of the family Deinocheiridae and is the only member of that clade known from Laramidia.

<i>Lalieudorhynchus</i> Extinct genus of synapsids

Lalieudorhynchus is an extinct genus of caseid synapsids that lived during the Guadalupian in what is now Southern France. The genus is only known by its type species, Lalieudorhynchus gandi, which was named in 2022 by Ralf Werneburg, Frederik Spindler, Jocelyn Falconnet, Jean-Sébastien Steyer, Monique Vianey-Liaud, and Joerg W. Schneider. Lalieudorhynchus is represented by a partial postcranial skeleton discovered in the Lodève basin in the central part of the Hérault department in the Occitanie region. It belongs to an individual measuring approximately 3.75 m (12.3 ft) in length. The degree of ossification of its bones, however, indicates that it was a late juvenile or still growing young adult. Based on the internal structure of its bones, the describing authors interpreted Lalieudorhynchus as a semiaquatic animal that may have had a lifestyle similar to that of hippopotamus, spending part of its time in water but returning to land for food, though the idea that caseids were semi-aquatic has been previously contested by other authors. It is geologically one of the youngest known representatives of the caseids. The phylogenetic analysis proposed by Werneburg and colleagues identified Lalieudorhynchus as a derived caseid closely related to the North American species "Cotylorhynchus" hancocki.

<i>Tridentinosaurus</i> Genus of controversial fossil reptiles

Tridentinosaurus is a dubious genus of extinct fossil reptile from the early Permian Regnana Formation of the Italian Alps. The genus contains a single species, T. antiquus. Tridentinosaurus represents one of the oldest known vertebrate fossils found in Italy. The only parts of the skeleton that are preserved are the long bones of the hind limbs, and the supposed soft tissue body outline is a forgery done with paint, though some genuine scales may also be preserved. Due to the poor preservation of the limb bones, the validity of the taxon is questionable.

References

  1. 1 2 3 4 Citton, P.; Ronchi, A.; Maganuco, S.; Caratelli, M.; Nicosia, U.; Sacchi, E.; Romano, M. (2019). "First tetrapod footprints from the Permian of Sardinia and their palaeontological and stratigraphical significance". Geological Journal. 54 (4): 1–15. doi:10.1002/gj.3285. S2CID   135216684.
  2. 1 2 3 4 5 6 Ronchi, A.; Sacchi, E.; Romano, M.; Nicosia, U. (2011). "A huge caseid pelycosaur from north-western Sardinia and its bearing on European Permian stratigraphy and palaeobiogeography". Acta Palaeontologica Polonica. 56 (4): 723–738. doi: 10.4202/app.2010.0087 .
  3. 1 2 3 4 5 6 Romano, M.; Nicosia, U. (2014). "Alierasaurus ronchii, gen. et sp. nov., a caseid from the Permian of Sardinia, Italy". Journal of Vertebrate Paleontology. 34 (4): 900–913. Bibcode:2014JVPal..34..900R. doi:10.1080/02724634.2014.837056. S2CID   85743001.
  4. 1 2 3 4 Romano, M.; Ronchi, A.; Maganuco, S.; Nicosia, U (2017). "New material of Alierasaurus ronchii (Synapsida, Caseidae) from the Permian of Sardinia (Italy), an dits phylogenetic affinities". Palaeontologia Electronica. 20.2.26A: 1–27. doi: 10.26879/684 . hdl: 11573/1045550 .
  5. 1 2 Romano, M.; Citton, P.; Maganuco, S.; Sacchi, E.; Caratelli, M.; Ronchi, A.; Nicosia, U. (2018). "New basal synapsid discovery at the Permian outcrop of Torre del Porticciolo (Alghero, Italy)". Geological Journal. 54 (3): 1–13. doi:10.1002/gj.3250. S2CID   133755506.
  6. ↑ McLoughlin, S. (2001). "The breakup history of Gondwana and its impact on pre-Cenozoic floristic provincialism". Australian Journal of Botany. 49 (3): 271–300. doi:10.1071/BT00023.
  7. ↑ Şengör, A.M.C. (1987). "Tectonics of the Tethysides: orogenic collage development in a collisional setting". Annual Review of Earth and Planetary Sciences. 15: 214–244. Bibcode:1987AREPS..15..213C. doi:10.1146/annurev.ea.15.050187.001241.
  8. ↑ Westphal, M.; Orsini, J.; Vellutini, P. (1976). "Le microcontinent Corso-Sarde, sa position initiale: données paléomagnétiques et raccords géologiques". Tectonophysics. 30 (1–2): 141–157. Bibcode:1976Tectp..30..141W. doi:10.1016/0040-1951(76)90142-6.
  9. 1 2 3 Cassinis, G.; Durand, M.; Ronchi, A. (2003). "Permian-Triassic continental sequences of Northwest Sardinia and South Provence: stratigraphic correlations and palaeogeographical implications". Bollettino della Società Geologica Italiana (Volume speciale) (2): 119–129.
  10. 1 2 3 4 5 Durand, M. (2006). "The problem of the transition from the Permian to the Triassic Series in southeastern France". In Lucas, S.G.; Cassinis, G.; Schneider, J.W. (eds.). Non-Marine Permian Biostratigraphy and Biochronology. London: Geological Society, Special Publication 265. pp. 281–296. ISBN   978-1-86239-206-9.
  11. ↑ "Le volcanisme rhyolitique permien du Sud de la France : Estérel, Corse, Briançonnais et Béarn". Planet-Terre. Pierre Thomas. Retrieved 14 September 2020.
  12. 1 2 3 Schneider, J.W.; Lucas, S.G.; Scholze, F.; Voigt, S.; Marchetti, L.; Klein, H.; Opluštil, S.; Werneburg, R.; Golubev, V.K.; Barrick, J.E.; Nemyrovska, T.; Ronchi, A.; Day, M.O.; Silantiev, V.V.; Rößler, R.; Saber, H.; Linnemann, U.; Zharinova, V.; Shen, S-Z. (2020). "Late Paleozoic–early Mesozoic continental biostratigraphy — Links to the Standard Global Chronostratigraphic Scale". Palaeoworld. 29 (2): 186–238. doi:10.1016/j.palwor.2019.09.001. S2CID   210316208.
  13. 1 2 3 4 Werneburg, R.; Spindler, F.; Falconnet, J.; Steyer, J.-S.; Vianey-Liaud, M.; Schneider, J.W. (2022). "A new caseid synapsid from the Permian (Guadalupian) of the Lodève basin (Occitanie, France)" (PDF). Palaeovertebrata. 45 (45(2)-e2): e2. doi:10.18563/pv.45.2.e2. S2CID   253542331.
  14. 1 2 Gand, G.; Durand, M. (2006). "Tetrapod footprint ichno-associations from French Permian basins. Comparisons with other Euramerican ichnofaunas". In Lucas, S.G.; Cassinis, G.; Schneider, J.W. (eds.). Non-Marine Permian Biostratigraphy and Biochronology. London: Geological Society, Special Publication 265. pp. 157–177. ISBN   978-1-86239-206-9.
  15. 1 2 Durand, M. (2008). "Permian to Triassic continental successions in southern Provence (France): an overview". Bollettino della Società Geologica Italiana. 127 (3): 697–716.
  16. ↑ Marchetti, L.; Klein, H.; Buchwitz, M.; Ronchi, A.; Smith, R.M.H.; De Klerk, W.J.; Sciscio, L.; Groenewald, G.H. (2019). "Permian-Triassic vertebrate footprints from South Africa: Ichnotaxonomy, producers and biostratigraphy through two major faunal crises". Gondwana Research. 72 (72): 139–168. Bibcode:2019GondR..72..139M. doi: 10.1016/j.gr.2019.03.009 . S2CID   133781923.
  17. ↑ Marchetti, L.; Voigt, S.; Lucas, S.G. (2019). "An anatomy-consistent study of the Lopingian eolian tracks of Germany and Scotland reveals the first evidence of the end-Guadalupian mass extinction at low paleolatitudes of Pangea". Gondwana Research. 73 (73): 32–53. Bibcode:2019GondR..73...32M. doi:10.1016/j.gr.2019.03.013. S2CID   146780505.
  18. ↑ Marchetti, L.; Logghe, A.; Mujal, E.; Barrier, B.; Montenat, C.; Nel, A.; Pouillon, J.-M.; Garrouste, R.; Steyer, J.-S. (2022). "Vertebrate tracks from the Permian of Gonfaron (Provence, Southern France) and their implication for the late Capitanian terrestrial extinction event". Palaeogeography, Palaeoclimatology, Palaeoecology. 599 (599): 111043. Bibcode:2022PPP...599k1043M. doi:10.1016/j.palaeo.2022.111043. S2CID   248597280.
  19. 1 2 Berman, D.S.; Maddin, H.C.; Henrici, A.C.; Sumida, S.S.; Scott, D.; Reisz, R.R. (2020). "New primitive Caseid (Synapsida, Caseasauria) from the Early Permian of Germany". Annals of Carnegie Museum. 86 (1): 43–75. doi:10.2992/007.086.0103. S2CID   216027787.
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