40-687: Dyrosauridae is a family of extinct neosuchian crocodyliforms that lived from the Campanian 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 (see locomotion below), with species inhabiting both freshwater and marine environments. Ocean-dwelling dyrosaurids were among
80-823: A clade based on the following seven synapomorphies or shared characters: Jouve et al. 2020 provide a comprehensive analysis of the relationships of dyrosaurids, shown below. Note the former dyrosaurids Sabinosuchus and Fortignathus are recovered as a pholidosaurid and a peirosaurid, respectively. Chenanisuchus lateroculi Anthracosuchus balrogus Cerrejonisuchus improcerus Phosphatosaurus gavialoides Sokotosuchus ianwilsoni Rodeosuchus machukiru Dorbignysuchus niatu Arambourgisuchus khouribgaensis Luciasuchus lurusinqa Dyrosaurus maghribensis Dyrosaurus phosphaticus Acherontisuchus guajiraensis Atlantosuchus coupatezi Rhabdognathus aslerensis Congosaurus bequaerti Rhabdognathus keiniensis Evidence for
120-412: A family— or whether a described family should be acknowledged— is established and decided upon by active taxonomists . There are not strict regulations for outlining or acknowledging a family, yet in the realm of plants, these classifications often rely on both the vegetative and reproductive characteristics of plant species. Taxonomists frequently hold varying perspectives on these descriptions, leading to
160-407: A fast-swimming ecology as well as some osteosclerosis which is a component of pachyostotic bone tissue. Osteoporosis is associated with a fully aquatic lifestyle whereas pachyostotic is not fully aquatic but is associated with fast swimming ecology. Therefore, dyrosaurs are semi-aquatic fast swimmers as indicated by their bone structure. Other evidence for near shore, semi-aquatic lifestyle is where
200-554: A lack of widespread consensus within the scientific community for extended periods. The continual publication of new data and diverse opinions plays a crucial role in facilitating adjustments and ultimately reaching a consensus over time. The naming of families is codified by various international bodies using the following suffixes: The taxonomic term familia was first used by French botanist Pierre Magnol in his Prodromus historiae generalis plantarum, in quo familiae plantarum per tabulas disponuntur (1689) where he called
240-405: A neotropical setting during a time when global temperatures were much warmer than they are today. In 1978, it was proposed that dyrosaurids lived as adults in the ocean but reproduced in inland freshwater environments. Remains belonging to small-bodied dyrosaurids from Pakistan were interpreted as juveniles. Their presence in inland deposits was viewed as evidence that dyrosaurids hatched far from
280-549: A part of the rostrum alongside an articulated piece of the mandible. All specimens were donated to the El Museo Muzquiz . The name Sabinosuchus is a combination of Sabinas , a town near the type locality, and the Greek Souchos (crocodile). The species name is likewise based on the area the specimen was found, referring to the state of Coahuila . Sabinosuchus was a longirostrine animal, meaning its snout
320-788: A putative dyrosaur, Schiller and colleagues make note that this assignment was poorly supported. Their initial phylogenetic tree is depicted below. Chenanisuchus lateroculi Anthracosuchus balrogus Sabinosuchus coahuilensis Cerrejonisuchus improcerus Hyposaurus rogersii Phosphatosaurus gavialoides Sokotosuchus lanwilsoni Arambourgisuchus khouribgaensis Dyrosaurus maghribensis Dyrosaurus phosphaticus Atlantosuchus coupatezi Guarinisuchus munizi Rhabdognathus aslerensis Rhabdognathus keiniensis By contrast, Schiller and colleagues identified several morphological features in Sabinosuchus which it shared with taxa used as outgroups in
360-437: A right femur and left tibia . In the left tibia, the cortex had a lamellar zonal bone with five lines of arrested growth (LAGs) which were spaced 300 mm apart, well as a clear vascular networks of primary osteons that decreased in density towards the membrane (periostially). The right femur had double LAGs and an EFS later as well as secondary osteons occurring in the deep cortex and the spongiosa. This tissue growth pattern
400-452: A single nasal bone . Typical in dyrosaurids is a single nasal element with a characteristic collection of small pits and a constant width until it widens to contact the lacrimal bones, then tapering off for a short distance until it meets the boundary of the frontals and prefrontals. Dyrosaurs have a premaxilla with shallow pits that extend posterior to the third maxillary alveoli. There are two premaxillae that are narrow as compared to
440-414: A snout to skull length of about 68% and the genus Rhabdognathus and Atlantosuchus , Dyrosaurus and Arambourgisuchus have the largest snout proportions of all dyrosaurids. Snout length was previously used it to establish dyrosaurid relationships, while considering the lengthening of the snout to be a ‘more evolved’ character. This was not congruent with Jouve's conclusion which was that the longest snout
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#1732772925344480-485: A total of twenty-one following the 2020 examination. Most dentary alveoli are circular in shape and range in diameter from 2.2–4.4 cm (0.87–1.73 in). The thirteenth to fifteenth differ significantly in arrangement however, emerging in a triangular pattern and are followed by closely spaced and smaller alveoli. The teeth are generally robust with a slight curvature towards the tip of the snout, but with better developed curviture and slight anteroposterior compression in
520-433: A way for the upper and lower jaws to alternate. Although they are still present in dyrosaurus phosphaticus, this feature of deep occlusal pits become less developed and broad. Dyrosaurus teeth are homodont, conical, long, and slender, with asymmetrically labial and lingual surfaces. Posterior teeth are shorter and more compressed than anterior tooth indicating that the tooth size decreased anterior to posterior. Dyrosaurs have
560-711: Is a genus of Mesoeucrocodylian , from the Maastrichtian Escondido Formation of Coahuila , Mexico , with Sabinosuchus coahuilensis as the type species . First described as a putative dyrosaurid by Shiller II et al. (2016), it was later recovered as a pholidosaurid by Jouve & Jalil (2020). Sabinosuchus was discovered by amateur paleontologist of the Palaeontologos Aficionados de Sabinas A.C. (PASAC) in 2002 in Mexico. All fossils of Sabinosuchus found by
600-812: Is a common characteristic of slow growing animals. Dyrosaurids are found in transitional marine sediments from the Late Cretaceous to lower Eocene. This family is known mainly from Maastrichthian deposits in New Jersey and the late Cretaceous to early Paleogene rock from the Tethys Sea in northern and western Africa. Fossils have also been found from the Paleocene and Eocene strata of Pakistan, as well as South America, Brazil, India, Southern Asia as well as coastal. Generally dyrosaurids are recovered from coastal and estuarine deposits through North Africa and
640-412: Is actually the primitive condition so the shorter or longer snout appears independently at least four times in dyrosaurid evolution. Dyrosaurids were once considered an African group, but discoveries made starting from the 2000s indicate they inhabited the majority of the continents. In fact, basal forms suggest that their cradle may have been North America. Jouve et al. (2005) diagnose Dyrosauridae as
680-431: Is classified between order and genus . A family may be divided into subfamilies , which are intermediate ranks between the ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae , but that family is commonly referred to as the "walnut family". The delineation of what constitutes
720-478: The Genera Plantarum of George Bentham and Joseph Dalton Hooker this word ordo was used for what now is given the rank of family. Families serve as valuable units for evolutionary, paleontological, and genetic studies due to their relatively greater stability compared to lower taxonomic levels like genera and species. Sabinosuchus Sabinosuchus (meaning " Sabinas crocodile")
760-733: The Umm Himar Formation in Saudi Arabia , inhabited estuarine environments near the coast. The recently named dyrosaurids Cerrejonisuchus and Acherontisuchus have been recovered from the Cerrejón Formation in northwestern Colombia , which is thought to represent a transitional marine-freshwater environment surrounded by rainforest more inland than the estuarine environment of the Umm Himar Formation. Cerrejonisuchus and Acherontisuchus lived in
800-441: The mandibular symphysis . The first alveoli preserved in the holotype were originally believed to be the first and second, however, reexamination by Jouve and Jalil later showed that these alveoli more likely housed the third and fourth dentary teeth given their lateral placement. These enlarged alveoli give the tip of a dentary a slightly rounded form. The better preserved of the two dentaries preserved nineteen alveoli, adding up to
840-615: The Maastrichtian of North America, the record of dyrosaurids became more complete by establishing a widespread distribution that appears to be maintained through the Paleocene and Eocene. Dyrosaurids have also been found from non-marine sediments. In northern Sudan , dyrosaurids are known from fluvial deposits, indicating that they lived in a river setting. Bones from indeterminate dyrosaurids have been found in inland deposits in Pakistan as well. Some dyrosaurids, such as those from
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#1732772925344880-750: The Middle East confirming their existence as semi-aquatic animals. Dyrosauridae had its greatest taxonomic diversity during the Early Paleogene but it appears as though the clade was able to obtain a greater and more widespread geographic distribution during the Late Cretaceous. The earliest records of dyrosaurids are either in or close to Africa with fragmentary occurrences from the Cenomanian of Sudan and Portugal and several other pre- Maastrichtian , Late Cretaceous discoveries in Egypt. Later, by
920-580: The authors. The fragmentary remains heavily limit the available characters for the phylogenetic analysis and even fewer are of value for determining its position within the clade. The matter is further complicated by the fact that the analysis recovered Sabinosuchus in a basal position within Dyrosauridae, being recovered as a sister taxa to the brevirostrine Anthracosuchus . However, very little mandibular remains are known from basal dyrosaurs, making comparison difficult. Overall, while first described as
960-480: The coast. A study on Cerrejonisuchus suggest this genus was more terrestrial than other dyrosaurids, and also shows that modern crocodylians are not good functional analogues for Dyrosauridae. [REDACTED] [REDACTED] [REDACTED] Family (biology) Family ( Latin : familia , pl. : familiae ) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy . It
1000-540: The family as a rank intermediate between order and genus was introduced by Pierre André Latreille in his Précis des caractères génériques des insectes, disposés dans un ordre naturel (1796). He used families (some of them were not named) in some but not in all his orders of "insects" (which then included all arthropods ). In nineteenth-century works such as the Prodromus of Augustin Pyramus de Candolle and
1040-564: The few marine reptiles to survive the Cretaceous–Paleogene extinction event . The dyrosaurids were a group of mostly marine, long jawed, crocodile-like quadrupeds up to 6 metres (20 ft) long. The largest dyrosaurid was probably Phosphatosaurus estimated at 9 m (30 ft) in length. Based on bone tissue evidence, it has been hypothesized that they were slow-growing near-shore marine animals with interlocking closed jaws, able to swim as well as walk on land. External nostrils at
1080-401: The fossils are found, often in transitional marine sediments. -using axial frequency swimming (that used primarily by extant crocodylians) with a greater undulatory motion and frequency of the tail due to highly developed musculature allowing a more powerful forward thrust. Dyrosaurids have a tissue pattern that is indicative of a slow-growth animal that was determined by careful analysis of
1120-412: The lateral margin of the skull. According to Jouve and Barbosa and perhaps depending on the age of the animal, each maxilla bears 13–19 teeth. An important feature of the dyrosaurid dentition are deep occlusal pits, present particularly in the posterior region of the maxillae that get less pronounced anteriorly. The pits are indicative of an interlocking closed jaw for dyrosaurids because the pits give
1160-437: The maxillary bones and extend in the two long maxilla bones which separated by the single nasal bone. The last premaxilla and first maxilla are widely separated by a fourth dentary tooth. Alveoli are widely spaced anteriorly and the space between them decreases posteriorly from the fifteenth alveolus with the diameter remaining constant. The maxilla is long (approx. two and a half times the length of jugal ) and forms most of
1200-522: The ocean. From the lower Eocene Oulad Abdoun Basin, there are very few juvenile dyrosaurids, but numerous similarly-sized adult specimens. This has furthered the assumption that juveniles lived in freshwater environments and adults lived in marine environments. Recently however, the large-bodied and fully mature dyrosaurids of the Cerrejón Formation have shown that some dyrosaurids lived their entire lives in inland environments, never returning to
1240-718: The original analysis, namely Sarcosuchus , Terminonaris and Elosuchus , typically considered to be pholidosaurids (although later analysis recovered Elosuchus as closer to Dyrosaurs). Additionally, the absence of a long, curved, retroarticular process was also seen as a possible indication that Sabinosuchus wasn't a dyrosaur, but this element is not preserved in the majority of derived dyrosaurs. A later study published by Jouve and Jalil in 2020 re-evaluated several taxa previously thought to be dyrosaurs or goniopholids, including Sabinosuchus . Their analysis placed several of these taxa within Pholidosauridae, extending
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1280-514: The posterior end of its snout and an internal naris in its pterygoid indicated a habit of hunting while swimming with the top of the head above the water, enabling it to breathe while stalking prey. Dyrosaurids are known to have a very characteristic skull shape with a long and thin snout that is approximately 68% of the total skull length. The most anterior part of the skull and snout is the external naris followed posteriorly by two premaxillae bones until they reach two maxillae bones separated by
1320-464: The range of the group into the Maastrichtian. In their analysis, Sabinosuchus claded together with Woodbinesuchus and Oceanosuchus . Importantly, the authors note that what was described as the first and second dentary alveoli in Schiller 2016 actually represented the third and fourth alveoli. Subsequently, the smaller seventh alveolous thought to indicate dyrosaurid affinities would actually be
1360-523: The rear portions of the jaw (at least from the seventeenth dentary tooth onward). The initial description by Schiller thought Sabinosuchus to be a dyrosaurid, a group of Neosuchians found in marine sediments of the Cretaceous to Early Eocene. This assignment was based on the size of the seventh dentary alveolus (smaller than the eight) and the proportions of the mandibular symphysis (approximately as wide as high). However, several problems were found by
1400-523: The reduction in bone tissue, many extant cetaceans and marine turtles have osteoporotic bone which enables them to be good swimmers. Pachyostotic bone is a general/local increase in skeletal mass which can be caused by osteosclerosis (inner compaction of bone), pachyostosis (hyperplasy of compact cortices) or pachyeosclerosis (combination of the two). Research on dyrosaur bone performed by Rafael César Lima Pedroso de Andrade and Juliana Manso Sayao revealed that this family had osteoporotic bone tissue indicative of
1440-427: The semi-aquatic life of dyrosaurids comes from careful analysis of bone structure. There are two types of structural bone organization that can occur in aquatic tetrapods: osteoporotic or pachyostotic . Osteoporotic bone is spongy and porous whereas pachyostotic involves an increase in skeletal mass. Spongy/porous bone such as osteoporotic is associated with faster swimming and better maneuverability in water because of
1480-575: The seventy-six groups of plants he recognised in his tables families ( familiae ). The concept of rank at that time was not yet settled, and in the preface to the Prodromus Magnol spoke of uniting his families into larger genera , which is far from how the term is used today. In his work Philosophia Botanica published in 1751, Carl Linnaeus employed the term familia to categorize significant plant groups such as trees , herbs , ferns , palms , and so on. Notably, he restricted
1520-639: The team stem from the Maastrichtian Escondido Formation , although earlier reports wrongfully believed them to stem from the underlying Olmos Formation . The material collected constitutes two individuals known from fragmentary remains that were later reassembled. Due to this the material was catalogued under several specimen numbers. The holotype material was initially catalogued as specimens PAS 945 to PAS 949 and PAS 952 once reassembled to form an almost complete specimen. The other specimen, catalogued as PAS 950 and PAS 951, represents
1560-549: The use of this term solely within the book's morphological section, where he delved into discussions regarding the vegetative and generative aspects of plants. Subsequently, in French botanical publications, from Michel Adanson 's Familles naturelles des plantes (1763) and until the end of the 19th century, the word famille was used as a French equivalent of the Latin ordo (or ordo naturalis ). In zoology ,
1600-461: Was proportionally long and slender. The nasal bones are unfused over their preserved length and covered in teardrop-shaped pits making it the most ornamented skull bone. The maxillae share similar ornamentation, with a dense clutter of circular pits present towards the posterior of the bone. The sides of the bone meanwhile are much smoother by comparison. The mandible is approximately 92 cm (36 in) long, less than half of that consisting of
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