Chenanisuchus ("Chenane crocodile") is a genus of dyrosaurid crocodyliform from the Late Cretaceous of Mali and the Late Palaeocene of Sidi Chenane in Morocco. It was described in 2005, after expeditions uncovered it in 2000.

 The type species is C. lateroculi ("lateralis", lateral; "oculi", eyes), in reference to the laterally facing eyes.

 Currently, Chenanisuchus is the most basal known dyrosaurid.

 Two specimens of C. lateroculi – OCP DEK-GE 262 (holotype, nearly complete skull with mandibular fragments) and OCP DEK-GE 61 (nearly complete skull) – come from the Sidi Chenane area in Morocco, which is Late Palaeocene (Thanetian) in age. Fossils of Chenanisuchus were also found in Maastrichtian age strata in Mali, what shows that Chenanisuchus survived the Cretaceous–Paleogene extinction event.

 Chenanisuchus lateroculi is referred to Dyrosauridae by Jouve et al. (2005), based on three morphological characters:

 - presence of occipital tuberosities;

 - presence of an anterolateral postorbital process;

 - large participation of the quadratojugal and surangular to the jaw joint.

 Chenanisuchus lateroculi has an estimated adult length between 4 and 4.5 meters, based on the 60 centimeter long skull. It has the shortest snout relative to the dorsal skull length among all dyrosaurids.

 Dyrosauridae is a family of extinct neosuchian crocodyliforms that lived from the Late Cretaceous (Maastrichtian) to the Eocene. Fossils of this group have been found in almost every continent, specifically Africa, Asia, Europe, North America and South America.

 Dyrosaurids were one of the few groups of marine reptiles to survive the End Cretaceous mass extinction. Several distinct genera have been documented, varying in overal size and cranial shape. Genera such as Dyrosaurus possessed long, slender jaws with numerous teeth (indicative of a primarily fish diet much like the extant gharial). It was a large animal, growing up to 6 meters (20 feet) in length. Even bigger, possibly up to 9 meters (30 feet), was Phosphatosaurus. More robust in its morphology, its jaws were relatively shorter, wider and much stronger, with large, partly rounded teeth. This jaw morphology would have been unsuitable for grasping slippery prey; instead a diet involving catching and crushing larger marine animals (such as sea turtles) is more likely.

 Dyrosaurids were once considered an African group, but more recent discoveries indicate they inhabited the majority of the continents. In fact, basal forms suggest that their cradle may have been North America.

 This group is poorly known, due to poor preservation of remains despite being relatively abundant. Despite this, Jouve et al. (2005) found Dyrosauridae to be a clade, based on seven synapomorphies:

 - Posteromedial wing of the retroarticular process dorsally situated ventrally on the retroarticular process;

 - Occipital tuberosities small;

 - Exoccipital participates largely to the occipital condyle;

 - Supratemporal fenestra anteroposteriorly strongly elongated;

 - Symphysis about as wide as high;

 - Quadratojugal participates largely to the cranial condyle for articulation with the jaw;

 - 4 premaxillary teeth.

 Most dyrosaurids were marine crocodiles. Dyrosaurids found from what is now northern and western Africa are thought to have inhabited the Trans-Saharan Sea, an epicontenental seaway that covered low-lying basins that formed during the late Mesozoic breakup of Africa and South America through crustal attenuation and fault reactivation, during a time of great global sea level elevation.

 Dyrosaurids have also been found from nonmarine 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 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 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 the ocean. 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 the coast.

 Dyrosauridae — семейство пресмыкающихся, входящих в группу Crocodylomorpha, живших с позднего мела (маастрихтский век) по эоцен. Ископаемые этой группы были обнаружены почти на всех континентах, в частности, в Африке, Азии, Европе, Северной Америке и Южной Америке. Представители данного семейства вырастали приблизительно до 6 метров и имели длинную вытянутую морду, приспособленную для ловли и поедания рыбы.

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Tags: Вымершие рептилии, Мел, архозавроморфы, архозавры, диапсиды, дирозавриды, крокодиломорфы, круротарзы, мезоэукрокодилии, неозухии, равизухии

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 Pholidosaurus is an extinct genus of neosuchian crocodylomorph. It is the type genus of the family Pholidosauridae. Fossils have been found from Germany and England. The genus is known to have existed during the Berriasian stage of the Early Cretaceous. Fossil material found from the Annero and Jydegård Formations in Skåne, Sweden and on the island of Bornholm, Denmark, have been referred to as a mesoeucrocodylian, and possibly represent the genus Pholidosaurus.

 An early description of the genus by Lydekker (1888) mentioned that the orbit is slightly smaller than the supratemporal fossa, the nasals reach the premaxillae, and the vomer appears on the palate. It is similar in appearance to and about as large as the modern gharial.

 The type species of Pholidosaurus is P. schaumburgensis, named in 1841 from the Wealden, or Hastings Sand, of Bückeburg, Germany. P. schaumburgensis was named on the basis of a natural mould of part of a thorax discovered in around 1830 from the Berriasian Obernkirchen Sandstone. This mould is known as IMGPGö 741-1. The individual that the mould belonged to is thought to have been around 25 centimetres (9.8 in) in length.

 Macrorhynchus is a junior synonym of Pholidosaurus. It was named in 1843 from the Wealden Group in southern England, with the type species being M. meyeri. Because M. meyeri bears a strong resemblance to Pholidosaurus schaumburgensis, it is now regarded as a species of Pholidosaurus. It was reassigned to the genus Pholidosaurus in 1887 by Richard Lydekker because of this synonymy, and also because the name Macrorhynchus was preoccupied by a genus of fish named in 1880. P. meyeri differs from P. schaumburgensis in that the bar separating the supratemporal fenestrae is rounded, while in the type species it is rounded.

 Several species of Pholidosaurus have been named in the past, but are no longer considered valid. These include P. decipiens and P. laevis. P. decipiens was constructed to describe a partial cranium, BMNH 28432, that was originally assigned to the new genus and species Petrosuchus laevidens by Richard Owen in 1878. Petrosuchus laevidens was based on this cranium and a mandibular ramus called BMNH 41099, both of which were collected from Swanage, England. A later study in 1911 concluded that the material belonged to two different species. BMNH 28432 was reassigned to Pholidosaurus and BMNH 41099 was referred to the retained name Petrosuchus laevidens. BMNH 28432 was designated as the lectotype of the new species Pholidosaurus decipiens, named in reference to Owen's oversight.

 Another species from England, P. purbeckensis, was originally described as a species of Steneosaurus in 1888. The holotype is an almost complete cranium, referred to as DORCM G97, missing the anterior portion of the rostrum. The skull was found from either Swanage or the Isle of Purbeck (hence the species name), although the exact locality from which the skull originated is not specified by the author of the original description. This material was also once referred to Macrorhynchus. The author of the 1888 description considered S. purbeckensis an intermediate form between Steneosaurus and Teleosaurus. However, in 2002, a new study proposed that S. purbeckensis belonged to P. decipiens. Because the name S. purbeckensis had seniority over P. decipiens, but not the genus Pholidosaurus, the name Pholidosaurus purbeckensis is considered to have priority.

 Another species of Pholidosaurus, P. laevis, was named in 1913 from Swanage, based on a partial cranium known as BMNH R3414. This has been considered a junior synonym of P. purbeckensis by both Salisbury et al. (1999) and Salisbury (2002).

 Richard Lydekker assigned Pholidosaurus to the family Goniopholididae in 1887 along with Hylaeochampsa, Theriosuchus, Goniopholis, and Petrosuchus because the vertebrae are amphicoelus and the orbit communicates with the lateral temporal fossa.

 Pholidosaurus has often been grouped with other longirostrine, or long-snouted, crocodylomorphs, including dyrosaurids and thalattosuchians. Buckley and Brochu (1999) concluded that Pholidosaurus, Sokotosuchus, Dyrosauridae, and Thalattosuchia formed a longirostrine clade that was the sister taxon to Crocodylia. However, Thalattosuchia was traditionally considered a more basal clade of crocodylomorphs, being a more basal lineage of Mesoeucrocodylia than dyrosaurids or Pholidosaurus, both of which were considered neosuchians. The results of the phylogenetic analysis by Buckley and Brochu (1999) were attributed to the similarity in characters associated with snout elongation seen in these crocodylomorphs, even though these characters may have been independently derived in each group. More recent studies have revealed Thalattosuchia as a more basal clade when dyrosaurids are removed from the data set.

 More recent studies show that Pholidosaurus is closely related to the Thalattosuchia, with both taxa closely related to a clade containing Terminonaris and the Dyrosauridae. In a phylogenetic analysis conducted by Sereno et al. (2001), Pholidosaurus was placed as a distant sister taxon to the other longirostrine crocodylomorphs, with Terminonaris and the newly named Sarcosuchus being closely related to one another and Dyrosaurus being the next closest taxon to the group. The later phylogenetic analysis of Brochu et al. (2002) again showed that Pholidosaurus was closely related to Thalattosuchia. In the study, both taxa formed a clade that was the sister taxon to a clade containing Sokotosuchus and Dyrosauridae.

 Pholidosaurus has recently been reassigned to the family Pholidosauridae, along with the genera Elosuchus, Sarcosuchus, and Termionaris. Jouve et al. (2006) concluded that Pholidosaurus was a pholidosaurid, although in their phylogenetic analysis, thalattosuchians were also included within the family, which would be considered paraphyletic without them. Jouve et al. (2006), like Buckley and Brochu (1999), attributed this result to phylogenetic problems that exist among longirostrine crocodylomorphs due to similarities in their morphology.

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Tags: Вымершие рептилии, Мел, архозавроморфы, архозавры, диапсиды, крокодиломорфы, круротарзы, мезоэукрокодилии, неозухии, равизухии, фолидозавриды

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