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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