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44-808: The Carnian was named in 1869 by Mojsisovics . It is unclear if it was named after the Carnic Alps or after the Austrian region of Carinthia ( Kärnten in German) or after the Carnia historical region in northeastern Italy. The name, however, was first used referring to a part of the Hallstatt Limestone cropping out in Austria . The base of the Carnian Stage is defined as the place in

88-460: A 2001 study of the biomechanics of the dinosaur Albertosaurus 's teeth, William L. Abler also examined a phytosaur's teeth, finding that it has had serrations so fine that they resembled a crack in the tooth. Albertosaurus had similarly crack-like serrations, but, at the base of each serration Abler discovered a round void , which would have functioned to distribute force over a larger surface area . This void, termed an ampulla, would hinder

132-539: A combination of the two. However, two taxa show slight adaptations towards hunting and consuming harder invertebrates. A study on phytosaur microwear patterns has found Mystriosuchus to line with soft invertebrate consumers, Nicrosaurus with hard invertebrate consumers and Smilosuchus and Machaeroprosopus with carnivores and piscivores. Phytosaurs have been traditionally held as rather "primitive" animals in regards to terrestrial locomotion, particularly in regards to archosaurs such as crocodilians , lacking

176-633: A distinct group of taxa (named Mystriosuchinae of Friedrich von Huene ) as other morphotypes such as Pseudopalatus are more closely related to Mystriosuchus than it is to the other long-snouted taxa. Brachyrostral ("short snouted") forms are the opposite, having a massive, broad snout, and very strong skulls and jaws. They are heterodont , as the front teeth are prominent fangs, and the rear teeth are blade-like for slicing food into chunks that can be swallowed easily. Taxa like this, such as Nicrosaurus and Smilosuchus , were powerful taxa that fed on stronger prey, such as terrestrial animals that came to

220-507: A recent study has suggested that Diandongosuchus is a basal phytosaur. If this is the case, this taxon offers more of a bridge between phytosaurs and earlier Archosauriformes. The earliest phytosaurs are traditionally classified in the genus Paleorhinus , now thought to be polyphyletic . Parasuchus and related basal species were widely distributed, meaning that phytosaurs dispersed across Pangea early on and there were probably few geographical barriers for their distribution; only in

264-458: A remarkable resemblance to modern crocodilians in size, appearance, and lifestyle, as an example of convergence or parallel evolution . The name "phytosaur" means "plant lizard", as the first fossils of phytosaurs were mistakenly thought to belong to plant eaters. For many years, phytosaurs were considered to be the most basal group of Pseudosuchia (crocodile-line archosaurs ), meaning that they were thought to be more closely related to

308-408: A secondarily terrestrial lifestyle, developing longer limb bones, straighter femora and a deeper pelvis, and indeed occurs in terrestrial or marginal lacustrine settings. Combined with its deep upper jaw, it probably led a similar lifestyle to terrestrial predatory crocodylomorphs like sebecians . Inversely, some dolichorostral forms like Mystriosuchus have become further specialised to life in

352-610: Is no established, standard usage for the Carnian subdivisions, thus, while in some regional stratigraphies a two-substage subdivision is common: others prefer a three-substage organization of the stage as follows: In the Tethys domain , the Carnian Stage contains six ammonite biozones: The Otischalkian land vertebrate faunachron corresponds to the early late Carnian, while the Adamanian land vertebrate faunachron corresponds to

396-617: Is not known if this is truly a member of the clade. Phytosaurs are known from many different morphologies, specifically with vastly different skull forms. These changes relate to the feeding and habits of the animals, not completely evolutionary modifications. Dolichorostral ("long snouted") phytosaurs have a long, slender snout with many conical teeth that are homodont (all the same). These taxa were most likely piscivores that were well adapted to capture fast aquatic prey, but not terrestrial animals. Paleorhinus , Rutiodon and Mystriosuchus are dolichorostral phytosaurs, but do not form

440-489: Is the standard generic name for these animals, despite the fact that these animals have been clearly shown to be carnivorous . Phytosaurs first appeared during the Carnian or Ladinian age, evolving from an unknown crurotarsan ancestor. There are no clear intermediate forms, as even the earliest known phytosaurs are highly specialized aquatic animals, unlike most contemporary archosauriforms that were terrestrial. However,

484-674: The Cephalopoda of the Austrian Triassic , and his publications include: With Melchior Neumayr (1845–1890) he conducted the Beiträge zur Paläontologie und Geologie Österreich-Ungarns (Contributions to the Palaeontology and Geology of Austria-Hungary). In 1862, with Paul Grohmann and Dr. Guido von Sommaruga, he founded the Österreichischer Alpenverein (Austrian Alpine Club ), and he also took part in establishing

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528-546: The Chinle Formation , but these "nests" are apparently the result of sandstone weathering. A recent study suggests they might have had parental care. When the first phytosaur fossils were found, it was not immediately obvious what kind of animal/species they were. The first phytosaur species known to science was named Phytosaurus cylindricodon – "plant lizard with cylindrical teeth" – by G. Jaeger in 1828 because he mistakenly believed that petrified mud fillings in

572-579: The German Alpine Club ( Deutscher Alpenverein ), which combined with the former in 1873. He is responsible for naming the stage on the geologic time scale known as the " Carnian ", after the Carnic Alps , in 1869. Phytosaur Parasuchia Huxley , 1875 Phytosaurs (Φυτόσαυροι in Greek , meaning 'plant lizard') are an extinct group of large, mostly semiaquatic Late Triassic archosauriform reptiles. Phytosaurs belong to

616-657: The Himalayas , and up to the island of Timor . The extreme land-sea distribution led to "mega-monsoons", i.e., an atmospheric monsoon regime more intense than the present one. As for most of the Mesozoic, there were no ice caps. Climate was mostly arid in the tropics, but an episode of wet tropical climate is documented at least in the Paleo-Tethys. This putative climatic event is called the " Carnian Pluvial Event ", its age being between latest early Carnian (Julian) and

660-658: The Ischigualasto-Villa Unión Basin in northwestern Argentina yielded a very important vertebrate association, including the oldest dinosaurian assemblage. The Lagerstätte of the Madygen Formation in Kyrgyzstan has provided over 20,000 fossil insects, vertebrates and flora. Johann August Georg Edmund Mojsisovics von Mojsvar Johann August Georg Edmund Mojsisovics von Mojsvár (18 October 1839 – 2 October 1907)

704-456: The end Triassic extinction event , about 200 Ma ago. There have been reports of phytosaur remains found in lowermost Jurassic rocks. Several teeth from Early Jurassic deposits in France have been identified as phytosaur teeth, but other studies argue they have either been misidentified or were reworked from Late Triassic into Early Jurassic deposits. In 1951, a partial upper jaw was discovered in

748-826: The order Phytosauria and are sometimes referred to as parasuchians . Phytosauria, Parasuchia, Parasuchidae, and Phytosauridae have often been considered equivalent groupings containing the same species. Some recent studies have offered a more nuanced approach, defining Parasuchidae and Phytosauridae as nested clades within Phytosauria as a whole. The clade Phytosauria was defined by Paul Sereno in 2005 as Rutiodon carolinensis and all taxa more closely related to it than to Aetosaurus ferratus , Rauisuchus tiradentes , Prestosuchus chiniquensis , Ornithosuchus woodwardi , or Crocodylus niloticus (the Nile crocodile). Phytosaurs were long-snouted and heavily armoured, bearing

792-539: The Early Norian sees new genera like Nicrosaurus and Pseudopalatus , both of which belong to the most derived clade of phytosaurs, the Pseudopalatinae . Later in the middle Norian the advanced and specialised fish-eater Mystriosuchus appears. Fossil remains of this widespread animal is known from Germany, northern Italy, and Thailand. Finally the large Redondasaurus in southwest North America and

836-647: The Early Jurassic Lower Lufeng Series in China and described as a new genus of phytosaur, Pachysuchus , but a study in 2012 reinterpreted the fossil as a sauropodomorph dinosaur. A fragment of a lower jaw from a longirostrine archosaur has been described from early Hettangian strata in the town of Watchet in Somerset , England. While teleosaurid thalattosuchians had similar longirostrine jaws to phytosaurs and were common in

880-547: The Ischigualato Formation (e.g. Herrerasaurus and Eoraptor ) and those from the Santa Maria Formation (e.g. Staurikosaurus and Buriolestes ) originated during the Carnian, around 230 Ma . In this stage the archosaurs became the dominant faunas in the world, evolving into groups such as the phytosaurs , rhynchosaurs , aetosaurs , and rauisuchians . The first dinosaurs (and

924-468: The Jurassic, they do not appear in the earliest Jurassic rocks. The mandible is more similar to those of known phytosaurs than to thalattosuchians, and likely belongs to a phytosaur closely related to the genus Mystriosuchus . The presence of phytosaurs in the earliest Jurassic may have prevented thalattosuchians from occupying similar ecological niches at that time. However, more recent work suggests that

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968-687: The Triassic. Fossils have been recovered from Europe , North America , India , Morocco , Thailand , Brazil , Greenland and Madagascar . Fossils attributed to phytosaurs have been found in Early Jurassic rocks, possibly extending their temporal range beyond the Triassic-Jurassic boundary. They may have also been present in rock layers dating to the Middle Triassic of China as evidenced by Diandongosuchus , however it

1012-412: The ability of the "crack" formed by the serration to propagate through the tooth. The phytosaur was found to lack adaptations for preventing its dental "cracks" from propagating. Abler examined another sort of prehistoric predator, Dimetrodon , and found that it also lacked adaptations for guarding against crack propagation. Based on their teeth, most phytosaur genera are carnivorous, piscivorous, or

1056-554: The base of the Carnian Stage, and is considered a characteristic species. A partial list of Carnian vertebrates is given below. Many Carnian vertebrates are found in Santa Maria Formation rocks of the Paleorrota geopark . The lower Carnian fauna of the San Cassiano Formation ( Dolomites , northern Italy ) has been studied since the 19th century. Fossiliferous localities are many, and are distributed mostly in

1100-451: The beginning of late Carnian (Tuvalian). In the marine realm, the Carnian saw the first abundant occurrences of calcareous nanoplankton, a morphological group including the coccolithophores . There are a few invertebrates which are typical and characteristic of the Carnian. Among molluscs, the ammonoid genus Trachyceras is exclusive to the lower Carnian (i.e., Julian of the two-substages subdivision, see above). The family Tropitidae and

1144-422: The belly reinforced with a dense arrangement of gastralia (abdominal ribs). Finally, and most noticeably, phytosaurs had nostrils placed near or above the level of the eyes, in contrast to crocodiles where the nostrils are near the end of the snout. This adaptation may have developed to allow them to breathe while the rest of the body was submerged. Unlike most crocodilians, phytosaurs have tooth serrations. In

1188-511: The crocodiles", as they resembled crocodiles to a great degree) was coined by Thomas Huxley in 1875 along with his discovery and naming of the Indian species Parasuchus hislopi (Chatterjee, 1978), on the basis of a partial snout. The specimen also is usually considered non-diagnostic, and the name Parasuchus replaced by Paleorhinus . Although the names Parasuchidae and Phytosauridae are variously still used by different specialists, "phytosaur"

1232-427: The crocodilians than to birds (the other living group of archosaurs). Some studies of the evolutionary relationships of early archosauriforms have suggested that phytosaurs evolved before the split between crocodile- and bird-line archosaurs and are a sister taxon of Archosauria. The most recent study retains the former way of classifying phytosaurs as pseudosuchians. Phytosaurs had a nearly global distribution during

1276-505: The erect gait seen in these, other pseudosuchians , dinosaurs and pterosaurs . However, the Apatopus ichnofossil shows that the animals did in fact have an erect gait like their archosaur relatives. Most phytosaurs are thought to be aquatic animals, and indeed most do show adaptations for such a lifestyle; swim tracks attributed to phytosaurs, for example, are known. However, at least Nicrosaurus seems to have evolved towards

1320-401: The genus Tropites appear at the base of the upper Carnian (Tuvalian). The bivalve genus Halobia , a bottom-dweller of deep sea environments, differentiated from Daonella at the beginning of this age. Scleractinian coral reefs, i.e., reefs with corals of the modern type, became relatively common for the first time in the Carnian. The earliest unequivocal dinosaurs , such as those from

1364-478: The jaw were herbivore teeth. The specimen is too poor to be diagnostic, and this species name is no longer valid. The name of the group – Phytosauria – was coined by the German paleontologist Hermann von Meyer in 1861, on the basis of this first species. The next species to be described was Belodon plieningeri by von Meyer in von Meyer and Plieninger 1844. The altogether more appropriate name Parasuchia ("alongside

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1408-462: The latest Carnian. The paleogeography of the Carnian was basically the same as for the rest of the Triassic. Most continents were merged into the supercontinent Pangaea , and there was a single global ocean, Panthalassa . The global ocean had a western branch at tropical latitudes called Paleo-Tethys . The sediments of Paleo-Tethys now crop out in southeastern Europe , in the Middle East , in

1452-450: The long snouted dolichorostral gavial . Various phytosaurs have crests and similar ornamentions in their snouts. Nicrosaurus has a ridge along the snout that would have supported a keratinous crest in life, while Mystriosuchus westphali has several bony crests. Despite their great similarities in appearance and lifestyle, there are still a number of minor differences that distinguish phytosaurs from true crocodiles. For one thing,

1496-692: The long-snouted (altirostral) Angistorhinopsis ruetimeyeri in Europe continued the group into the Rhaetian . Phytosaur footprints (the ichnotaxon Apatopus ) are also known from the latest Rhaetian of the East Coast of USA (the Newark Supergroup ) (Olsen et al. 2002). This indicates that phytosaurs continued as successful animals until the very end of the Triassic, when, along with many other large crurotarsan reptiles, they were killed off by

1540-437: The phytosaur ankle structure is much more primitive than that of any crocodile. Also, phytosaurs lack the bony secondary palate that enables crocodiles to breathe even when the mouth is full of water. However, it is possible that phytosaurs had a fleshy palate, as many Mesozoic crocodiles are presumed to have had. Phytosaurs were even better armoured than crocodiles, protected by heavy bony scutes (often found as fossils), and

1584-407: The presence of multiple sinuses, smaller cerebral hemispheres and smaller endosseous labyrinths. The similarities are considered to be plesiomorphic in relation to the ancestral archosauriform design, lacking many features seen in avemetatarsalians , though convergence in terms of lifestyle might also play a role. No phytosaur eggs have been found so far. There are pits associated with footprints in

1628-555: The pterosaur Carniadactylus ) also appeared in this stage, and though at the time they were small and insignificant, they diversified rapidly and would dominate the fauna for the rest of the Mesozoic . On the other hand, the therapsids , which included the ancestors of mammals , decreased in both size and diversity, and would remain relatively small until the extinction of the dinosaurs. Conodonts were present in Triassic marine sediments. Paragondolella polygnathiformis appeared at

1672-406: The southernmost regions are they rare, possibly due to increased aridity. A somewhat more advanced and larger form, Angistorhinus appears at the same time or soon after. Later in the Carnian, both these animals were replaced by more specialised forms like Rutiodon , Leptosuchus , and the huge Smilosuchus (Lucas 1998). The Carnian-Norian extinction meant that these animals died off, and

1716-669: The stratigraphic record where the ammonite species Daxatina canadensis first appears. The global reference profile for the base is located at the Stuores-Wiesen near Badia in the Val Badia in the region of South Tyrol , Italy . The top of the Carnian (the base of the Norian) is at the bases of the ammonite biozones of Klamathites macrolobatus or Stikinoceras kerri and the conodont biozones of Metapolygnathus communisti or Metapolygnathus primitius . There

1760-501: The surroundings of Cortina d'Ampezzo and in the high Badia Valley, near the village of San Cassiano , after which the formation was named. This fauna is extremely diverse, including ammonoids, gastropods, bivalves, echinoderms, calcareous sponge , corals, brachiopods , and a variety of less common fossils. A collection of this fauna is exposed in the "Museo delle Regole", a museum in Cortina d'Ampezzo. The Ischigualasto Formation of

1804-400: The water to drink. Altirostral ("high snouted") animals are intermediate between the two distinct types. They had heterodont dentition but not as extremely developed as the brachyrostral type. Pseudopalatus is an altirostral phytosaur, and was most likely a generalist feeder. Modern crocodilians exhibit a similar morphological diversity, for example the broad snouted altirostral alligator and

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1848-412: The water, and occurred in marine environments. A skeleton of Mystriosuchus planirostris , found in a marine setting and with evidence of little post-mortem transportation – indicating that it died either at sea or in a freshwater environment nearby – shows that this animal had paddle-like limbs, less adapted for terrestrial locomotion than in most other phytosaurs. Furthermore, the tail of Mystriosuchus

1892-730: Was an Austro-Hungarian geologist and palaeontologist . Mojsisovics was the son of the surgeon Georg Mojsisovics von Mojsvar (1799–1860). His name in Hungarian: Ödön. He was born in Vienna . He studied law in Vienna University , taking his doctorate degree in 1864, and in 1867 he entered the Geological Institute , becoming chief geologist in 1870 and vice-director in 1892. He retired in 1900 and died at Mallnitz on 2 October 1907. Mojsvar paid special attention to

1936-412: Was laterally compressed and could have been used in propulsion. Scans on various phytosaur braincases suggest that these animals generally had long olfactory tracts, weakly demarcated cerebral regions, dorsoventrally short endosseous labyrinths and various sinuses, including large antorbital and dural venous ones; the general bauplan is vaguely similar to that of crocodilians, but differs significantly in

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