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Aetosaur
Aetosaurs () are heavily armored reptiles belonging to the extinct order Aetosauria (; from Greek, (aetos, "eagle") and (, "lizard")). They were medium- to large-sized omnivorous or herbivorous pseudosuchians, part of the branch of archosaurs more closely related to crocodilians than to birds and other dinosaurs. All known aetosaurs are restricted to the Late Triassic, and in some strata from this time they are among the most abundant fossil vertebrates. They have small heads, upturned snouts, erect limbs, and a body ornamented with four rows of plate-like osteoderms (bony scutes). Aetosaur fossil remains are known from Europe, North and South America, parts of Africa, and India. Since their armoured plates are often preserved and are abundant in certain localities, aetosaurs serve as important Late Triassic tetrapod index fossils. Many aetosaurs had wide geographic ranges, but their stratigraphic ranges were relatively short. Therefore, the presence of particular aetosaurs can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aetosaur Skull Diagrams
Aetosaurs () are heavily armored reptiles belonging to the extinct order (biology), order Aetosauria (; from Ancient Greek, Greek, (aetos, "eagle") and (, "lizard")). They were medium- to large-sized Omnivore, omnivorous or Herbivore, herbivorous Pseudosuchia, pseudosuchians, part of the branch of archosaurs more closely related to crocodilians than to birds and other dinosaurs. All known aetosaurs are restricted to the Late Triassic, and in some strata from this time they are among the most abundant fossil vertebrates. They have small heads, upturned snouts, erect limbs, and a body ornamented with four rows of plate-like Osteoderm, osteoderms (bony scutes). Aetosaur fossil remains are known from Europe, North America, North and South America, parts of Africa, and India. Since their armoured plates are often preserved and are abundant in certain localities, aetosaurs serve as important Late Triassic tetrapod index fossils. Many aetosaurs had wide geographic ranges, but their stra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aetosaurinae
Aetosaurinae is one of the two main clades of aetosaurs, the other being Desmatosuchia. It is a stem-based taxon defined as all aetosaurs more closely related to ''Aetosaurus'' than ''Desmatosuchus''. Aetosaurinae currently comprises ''Aetosaurus,'' similar forms such as '' Coahomasuchus'' and '' Stenomyti'', and the widespread and successful aetosaur clade Typothoracinae. Previous usage Aetosaurinae was originally named in 2000, as a subfamily solely including ''Aetosaurus'', which was assumed to be the earliest-diverging aetosaur. In 2007, it was extended to include the subfamily Typothoracinae as well as various basal aetosaurs which were not clearly within Desmatosuchinae. These proposed non-typothoracine aetosaurines included ''Coahomasuchus'', ''Neoaetosauroides'', ''Aetosauroides'', ''Stagonolepis robertsoni,'' and ''"Stagonolepis"'' (''Calyptosuchus'') ''wellesi''. As a subfamily containing practically all non-desmatosuchine aetosaurs, Aetosaurinae was poorly-supported ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aetosauroides
''Aetosauroides'' (meaning "''Aetosaurus''-like") is an extinct genus of aetosaur from the Late Triassic of South America. It is one of four aetosaurs known from South America, the others being ''Neoaetosauroides'', '' Chilenosuchus'' and ''Aetobarbakinoides''. Three species have been named: the type species ''A. scagliai'', ''A. subsulcatus'' and ''A. inhamandensis''. Fossils have been found in the Cancha de Bochas Member of the Ischigualasto Formation in the Ischigualasto-Villa Unión Basin in northwestern Argentina and the Santa Maria Formation in the Paraná Basin in southeastern Brazil. The strata date to the late Carnian and early Norian stages, making ''Aetosauroides'' one of the oldest aetosaurs. Description Most individuals of ''Aetosauroides'' measured around in length, with one large individual reaching (with histology suggesting an age of 23 years). Sexual maturity was probably reached at in length, although these individuals were not yet fully grown. Sexual dim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polesinesuchus
''Polesinesuchus'' is an extinct genus of stagonolepidid aetosaur known from the Late Triassic of southern Brazil. Fossils have been found from the Santa Maria Supersequence of the late Carnian and early Norian stages, making ''Polesinesuchus'' one of the oldest aetosaurs. It contains a single species, ''Polesinesuchus aurelioi'', the fifth aetosaur species known from South America to date. Anatomical evidence suggests that ''Polesinesuchus'' likely represents a juvenile individual of the contemporary ''Aetosauroides''. Discovery ''Polesinesuchus'' was first named by Lúcio Roberto-da-Silva, Julia B. Desojo, Sérgio F. Cabreira, Alex S. S. Aires, Rodrigo T. Müller, Cristian P. Pacheco and Sérgio Dias-da-Silva in 2014 and the type species is ''Polesinesuchus aurelioi''. It is known solely from its holotype specimen, a partially articulated partial skeleton. It is composed of the parietal bone and the braincase as well as postcranial elements including cervical, dorsal, sacral a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desmatosuchus
''Desmatosuchus'' (, from Greek δεσμός ''desmos'' 'link' + σοῦχος ''soûkhos'' 'crocodile') is an extinct genus of archosaur belonging to the Order Aetosauria. It lived during the Late Triassic. Description ''Desmatosuchus'' was a large quadrupedal reptile upwards of to in lengthvon Baczko, M. B., Desojo, J. B., Gower, D. J., Ridgely, R., Bona, P., & Witmer, L. M. (2021)New digital braincase endocasts of two species of Desmatosuchus and neurocranial diversity within Aetosauria (Archosauria: Pseudosuchia) The Anatomical Record, 1–20. https://doi.org/10.1002/ar.24798 and in weight. Its vertebral column had amphicoelus centra and 3 sacral vertebrae. This archosaur's most distinguishing anatomical characteristics were its scapulae which possessed large acromion processes commonly referred to as "shoulder spikes". The forelimbs were much shorter than the hindlimbs, with humeri less than two-thirds the length of the femurs. The pelvic girdle consisted of a long pub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudosuchia
Pseudosuchia is one of two major divisions of Archosauria, including living crocodilians and all archosaurs more closely related to crocodilians than to birds. Pseudosuchians are also informally known as "crocodilian-line archosaurs". Prior to 2011, the clade Pseudosuchia was often called Crurotarsi in reference to the crurotarsal ankle found in almost all members of the group, which traditionally included phytosaurs, ornithosuchids, and suchians. However, a major 2011 study of Triassic archosaur relations proposed that phytosaurs were not closely related to other traditional "crurotarsans", at least compared to "bird-line archosaurs" (Avemetatarsalians) such as pterosaurs and dinosaurs. As a result, the possession of a crurotarsal ankle was considered a plesiomorphic ("primitive") feature retained by pseudosuchians. Crurotarsi now refers to a broader group of reptiles including Pseudosuchia, Phytosauria, and Avemetatarsalia. Despite Pseudosuchia meaning "false crocodiles", th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desmatosuchinae
Desmatosuchinae is a major subfamily of aetosaurs within the clade Desmatosuchia. It is a stem-based taxon defined as all aetosaurs more closely related to ''Desmatosuchus'' than to ''Stagonolepis,'' ''Aetosaurus'', or '' Paratypothorax''. The clade Desmatosuchinae has often been restricted to a few closely-related aetosaurs with spiny armor, such as ''Desmatosuchus'', ''Longosuchus'', and ''Lucasuchus''. It was later expanded to include a number of ''Stagonolepis''-like aetosaurs with less specialized armor. Under this more expansive usage, the strongly-supported clade encompassing "traditional" desmatosuchines (''sensu stricto'') was given a new name, Desmatosuchini. Synapomorphies that diagnose this clade can be found in the osteoderms. These include tongue-and-groove articulations for lateral plates present in dorsal presacral paramedian plates and large spikes on the lateral cervical, dorsal, and caudal plates. Timeline of generic descriptions ImageSize = width:1000px ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stagonolepis
''Stagonolepis'' is an extinct genus of stagonolepidid aetosaur known from the Late Triassic (Carnian stage) Hassberge Formation of Germany, the Drawno Beds of Poland, and the Lossiemouth Sandstone of Scotland. Supposed fossils from North and South America have been placed into their own genera, ''Calyptosuchus'' and ''Aetosauroides'', respectively. Description ''Stagonolepis robertsoni'' was about long. It was a quadrupedal animal covered in thick armoured scales that ran down the length of its body. A slow-moving browser, it would have used this heavy body armour to repel attacks from contemporary thecodont carnivores. ''Stagonolepis'' had a very small head for its size; it was only , accounting for less than 10% of the total body length. It had no teeth in the front of its jaws, but instead had a beak-like tip that arched upwards. This would have allowed it to uproot plants in a similar manner to a modern pig. The peg-like teeth at the back of its mouth would have been ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calyptosuchus
''Calyptosuchus'' (meaning "covered crocodile") is an extinct genus of aetosaur from the Late Triassic of North America. Like other aetosaurs, it was heavily armored and had a pig-like snout used to uproot plants. Description ''Calyptosuchus'' was estimated to have been four metres long, or possibly larger, with a maximum carapace width of almost seventy centimetres. The osteoderms were not entirely fused. Each row of the osteoderms corresponded to one vertebra, and comprised four dorsal osteoderms. Two small squarish osteoderms formed the outside of the row (about 10 by 10 cm), and two much broader osteoderms (approximately 20 by 10 cm) formed the inside of the row and covered most of the back. Each of the lateral osteoderms have a raised boss towards the centre at the posterior end of the osteoderm, and are almost bent around the side of the creature, with a dorsal flange along the back contacting the paramedian (dorsal) osteoderms and a lateral flange running a littl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Revueltosaurus
''Revueltosaurus'' ("Revuelto lizard") is an extinct genus of suchian pseudosuchian from Late Triassic (late Carnian to middle Norian stage) deposits of New Mexico, Arizona and North Carolina, United States. Many specimens, mostly teeth, have been assigned to ''Revueltosaurus'' over the years. Currently, three species are included in this genus, all of which were originally thought to represent monospecific genera of basal ornithischian dinosaurs. It was 1 meter (3.3 feet) long. Species ''Revueltosaurus callenderi'' ''R. callenderi'' was named by Adrian P. Hunt in 1989 and it is the type species of the genus. The generic name honors its type locality, Revuelto Creek, Quay County of New Mexico. Revuelto is derived from Spanish ''revuelta'', "revolution", in reference to the importance of the Late Triassic period for terrestrial vertebrate evolution. The specific name honours the director of the New Mexico Museum of Natural History Jonathan F. Callender. ''R. callenderi'' was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Triassic
The Late Triassic is the third and final epoch (geology), epoch of the Triassic geologic time scale, Period in the geologic time scale, spanning the time between annum, Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch and followed by the Early Jurassic Epoch. The corresponding series (stratigraphy), series of rock beds is known as the Upper Triassic. The Late Triassic is divided into the Carnian, Norian and Rhaetian Geologic time scale, Ages. Many of the first dinosaurs evolved during the Late Triassic, including ''Plateosaurus'', ''Coelophysis'', and ''Eoraptor''. The Triassic–Jurassic extinction event began during this epoch and is one of the five major mass extinction events of the Earth. Etymology The Triassic was named in 1834 by Friedrich August von Namoh, Friedrich von Alberti, after a succession of three distinct rock layers (Greek meaning 'triad') that are widespread in southern Germany: the lower Buntsandstein (colourful sandstone'')'', t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osteoderm
Osteoderms are bony deposits forming scales, plates, or other structures based in the dermis. Osteoderms are found in many groups of extant and extinct reptiles and amphibians, including lizards, crocodilians, frogs, temnospondyls (extinct amphibians), various groups of dinosaurs (most notably ankylosaurs and stegosaurians), phytosaurs, aetosaurs, placodonts, and hupehsuchians (marine reptiles with possible ichthyosaur affinities). Osteoderms are uncommon in mammals, although they have occurred in many xenarthrans (armadillos and the extinct glyptodonts and mylodontid and scelidotheriid ground sloths). The heavy, bony osteoderms have evolved independently in many different lineages. The armadillo osteoderm is believed to develop in subcutaneous dermal tissues. These varied structures should be thought of as anatomical analogues, not homologues, and do not necessarily indicate monophyly. The structures are however derived from scutes, common to all classes of amniotes and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
