Mauritanichthys Temporal range: Late Triassic, | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | † Redfieldiiformes |
Family: | † Redfieldiidae |
Genus: | † Mauritanichthys Martin, 1980 |
Species: | †M. rugosus |
Binomial name | |
†Mauritanichthys rugosus Martin, 1980 | |
Mauritanichthys is an extinct genus of palaeoniscoid redfieldiid ray-finned fish from Morocco. It is only known from the Timezgadiouine Formation location within the Atlas Mountains. The deposits date back to the Late Triassic, more specifically the Carnian. It was a small, fusiform fish with a reduced postrostral very similar in morphology to another member of the family Lasalichthys . There is only a single known species being M. rugosus.
Though the exact time of the collection of the specimens isn't known, Mauritanichthys was described in 1980 by Michel Martin and is known by multiple specimens including the holotype, ALM 312. These specimens were found at locality 11 of the Timezgadiouine Formation. This locality is a part of the base member of the Irohalene Member (also referred to as "T5") and has yield both body and ichnofossils of a large amount of animals. [1] The name Mauritanichthys derives from both Ancient Greek and Latin; being a combination between mauritanicus, Latin for "from Morocco" and ichthys, a word derived from the Ancient Greek word for fish. The species name "rugosus" is derived from the Latin word for rough or wrinkled. [1]
Mauritanichthys was a small, fusiform fish though it was much larger than other members of the group, measuring to a total of 15 cm (5.9 in.).
Mauritanichthys had a skull similar to other redfieldiiforms with rectangular dermosphenotic and dermopterotic bones with the dermosphenotic and multiple infraorbitals making up parts of the orbit. Along with those bones, the adnasal forms the front of the orbits. The postrostral is small is flanked by the nasal bones. Like a number of other redfieldiiforms, Mauritanichthys had a number of tubercles on the front of the skull. The maxilla slender though increases in height below the preopercle and contains a set of large teeth. The opercular region is made up of the operculum and suboperculum with the these bones being a little taller than they are wide. Just like other members of the group, the branchiostegal elements are reduced with only one being present. [2]
Mauritanichthys had a tall body, with the tallest section being right behind the head. The squamation was made of at least 40 rows, made up of 16-17 scales each depending on the part of the body. The pectoral fins were made up of seven to eight unsegmented rays and a pair of fringing fulcra. The only other fin to be preserved would be the pelvic fins which were made up of seven to eight rays that, unlike the pectoral fins, were segmented. [2]
The relationship between Mauritanichthys and Lasalichthys had been suggested from the original description due to the extreme similarities in the skulls. [2] Even with this, the interrelationships of the group were not expanded upon until Schaffer (1984) where this relationship was confirmed along with the their relation to other members of the group described at the time. Shown below is the phylogenic tree from said paper. [3]
Like all other known redfieldiiformes, Mauritanichthys would have lived in freshwater environments with the base part of the Irohalene Member representing the alluvial plain. This plain would have been made up of a large amount of meandering rivers and large floodplains. The humid area would have had a warm, seasonal climate which would have flooded at certain points of the year. [4] Younger strata show a gradual decrease in borrows and other ichnofossils, with it representing a change to more arid conditions. [5] A large diversity of vertebrates have been found in the represented strata including dicynodonts, archosaurs, and temnospondyls. Some of the more notable members of this paleobiota including the metoposaurid Dutuitosaurus and the silesaur Diodorus . [1] [6]
Postosuchus, meaning "Crocodile from Post", is an extinct genus of rauisuchid reptiles comprising two species, P. kirkpatricki and P. alisonae, that lived in what is now North America during the Late Triassic. Postosuchus is a member of the clade Pseudosuchia, the lineage of archosaurs that includes modern crocodilians. Its name refers to Post Quarry, a place in Texas where many fossils of the type species, P. kirkpatricki, were found. It was one of the apex predators of its area during the Triassic, larger than the small dinosaur predators of its time. It was a hunter which probably preyed on large bulky herbivores like dicynodonts and many other creatures smaller than itself.
Azendohsaurus is an extinct genus of herbivorous archosauromorph reptile from roughly the late Middle to early Late Triassic Period of Morocco and Madagascar. The type species, Azendohsaurus laaroussii, was described and named by Jean-Michel Dutuit in 1972 based on partial jaw fragments and some teeth from Morocco. A second species from Madagascar, A. madagaskarensis, was first described in 2010 by John J. Flynn and colleagues from a multitude of specimens representing almost the entire skeleton. The generic name "Azendoh lizard" is for the village of Azendoh, a local village near where it was first discovered in the Atlas Mountains. It was a bulky quadruped that unlike other early archosauromorphs had a relatively short tail and robust limbs that were held in an odd mix of sprawled hind limbs and raised forelimbs. It had a long neck and a proportionately small head with remarkably sauropod-like jaws and teeth.
Poposaurus is an extinct genus of pseudosuchian archosaur from the Late Triassic of the southwestern and eastern United States. It belongs to the clade Poposauroidea, an unusual group of Triassic pseudosuchians that includes sail-backed, beaked, and aquatic forms. Fossils have been found in Wyoming, Utah, Arizona, Texas, and Virginia. Except for the skull, most parts of the skeleton are known. The type species, P. gracilis, was described and named by Maurice Goldsmith Mehl in 1915. A second species, P. langstoni, was originally the type species of the genus Lythrosuchus. Since it was first described, Poposaurus has been variously classified as a dinosaur, a phytosaur, and a "rauisuchian".
Metoposaurus meaning "front lizard" is an extinct genus of stereospondyl temnospondyls, known from the Late Triassic of Germany, Italy, Poland, and Portugal. This mostly aquatic animal possessed small, weak limbs, sharp teeth, and a large, flat head. This highly flattened creature mainly fed on fish, which it captured with its wide jaws lined with needle-like teeth. Many Metoposaurus mass graves have been found, probably from creatures that grouped together in drying pools during drought.
Hesperosuchus is an extinct genus of crocodylomorph reptile that contains a single species, Hesperosuchus agilis. Remains of this pseudosuchian have been found in Late Triassic (Carnian) strata from Arizona and New Mexico. Because of similarities in skull and neck anatomy and the presence of hollow bones Hesperosuchus was formerly thought to be an ancestor of later carnosaurian dinosaurs, but based on more recent findings and research it is now known to be more closely related to crocodilians rather than dinosaurs.
Dromicosuchus is an extinct genus of sphenosuchian, a type of basal crocodylomorph, the clade that comprises the crocodilians and their closest kin. It was found in Upper Triassic rocks of North Carolina, United States, and is known from a nearly complete skull and partial skeleton. This specimen is unusual in that it was found beneath the skeleton of a larger rauisuchian and has apparent bite damage, suggesting that it was attacked by the larger carnivore before both died and were buried together.
Moghreberia is an extinct genus of dicynodont predicted to have lived only in the mid-Triassic, primarily during the early middle Carnian and found only in the Argana Basin of Morocco. Moghreberia belonged to the Stahleckeriidae family, a group of anomodont therapsids and is most commonly known by its species Moghreberia nmachouensis. Its name is derived from the Arabic phrase al-Maghrib al-Aqsa meaning “the far west”, a term used by Arabic scholars to refer to the approximate region of Morocco, the area in which this animal’s fossil was first discovered. The extinction of many dicynodonts has been attributed to pressures of the Carnian Pluvial Episode, which occurred around 234-232 Ma and generated major ecological and climate changes for years to come.
Arganodus is an extinct genus of freshwater lungfish that had a wide global distribution throughout much of the Triassic period, with a single species surviving across Gondwana into the Cretaceous. It is the only member of the family Arganodontidae, although it is sometimes placed in the Ceratodontidae or synonymized with the genus Asiatoceratodus.
Luperosuchus is an extinct genus of loricatan pseudosuchian reptile which contains only a single species, Luperosuchus fractus. It is known from the Chañares Formation of Argentina, within strata belonging to the latest Ladinian stage of the late Middle Triassic, or the earliest Carnian of the Late Triassic. Luperosuchus was one of the largest carnivores of the Chañares Formation, although its remains are fragmentary and primarily represented by a skull with similarities to Prestosuchus and Saurosuchus.
The Argana Group is a Permian to Triassic geological group in the western High Atlas northeast of Agadir, Morocco. Sometimes known as the Argana Formation, it contains eight geological members often divided into three formations. They include the Late Permian Ikakern Formation, the Early Triassic to Carnian Timezgadiouine Formation (T3-T5), and the Late Triassic Bigoudine Formation (T6-T8). Ornithischian tracks are geographically located in Marrakesh province. Indeterminate theropod remains and tracks are geographically located in Marrakesh province.
Arganasuchus is an extinct genus of "rauisuchian" (loricatan) archosaur. It is known from a single species, Arganasuchus dutuiti. Fossils of this genus have been found in Upper Triassic rocks of the Argana Basin, Morocco. Though its remains were initially referred to Ticinosuchus when discovered during the 1970s, in 2007 it was identified as a distinct genus with unique features of the pubis and maxilla. Arganasuchus also had several anatomical details in common with Batrachotomus, Fasolasuchus, and Postosuchus, though its relations with other loricatans remains unresolved. Arganasuchus is considered a carnivore due to its large, knife-shaped teeth.
Atopocephala is an extinct genus of prehistoric freshwater ray-finned fish that lived during the Middle Triassic epoch. It contains a single species, A. watsoni from the Karoo Supergroup of South Africa. A potential indeterminate species was known from the Timezgadiouine Formation of Morocco, but is now considered an indeterminate actinopterygian.
Chanaresuchus is an extinct genus of proterochampsid archosauriform. It was of modest size for a proterochampsian, being on average just over a meter in length. The type species is Chanaresuchus bonapartei was named in 1971. Its fossils were found in from the early Carnian-age Chañares Formation in La Rioja Province, Argentina. Chanaresuchus appears to be one of the most common archosauriforms from the Chañares Formation due to the abundance of specimens referred to the genus. Much of the material has been found by the La Plata-Harvard expedition of 1964–65. Chanaresuchus is the most well-described proterochampsid in the subfamily Rhadinosuchinae.
Dipteronotus is an extinct genus of marine stem-neopterygian ray-finned fish that existed during the Middle and Late Triassic epochs in what is now Europe and Morocco. As a typical feature, it had several ridge scales in front of its dorsal fin that created a spine-like structure.
Diodorus is a genus of silesaurid dinosauromorph that lived during the Late Triassic in what is now Morocco. Fossils were discovered in the Timezgadiouine Formation of the Argana Basin, and were used to name the new genus and species Diodorus scytobrachion. The genus name honors the mythological king Diodorus and the ancient historian Diodorus Siculus; the specific name is ancient Greek for 'leathery arm' and also honors the mythographer Dionysius Scytobrachion. The holotype specimen is a partial dentary bone (front of the lower jaw), and assigned specimens include isolated teeth, two humeri (upper arm bones), a metatarsal (foot bone), and femur (thigh bone).
Diandongosuchus is an extinct genus of archosauriform reptile, possibly a member of the Phytosauria, known from the Middle Triassic of China. The type species Diandongosuchus fuyuanensis was named in 2012 from the Zhuganpo Formation of Yunnan Province. It is a marine species that shows similarities with another Chinese Triassic species called Qianosuchus mixtus, although it has fewer adaptations toward marine life. It was originally classified as the basal-most member of the pseudosuchian clade Poposauroidea. However, a subsequent study conducted by Stocker et al. indicated it to be the basalmost known phytosaur instead.
Redfieldiiformes is an extinct order of ray-finned fish (actinopterygians) which lived from the Early Triassic to Early Jurassic. Redfieldiiforms were fairly typical Triassic fish in overall anatomy. They had a fusiform body shape with thick, ganoine-covered scales. The dorsal and anal fins were large, positioned opposite from each other, and shifted back, close to the tail. The caudal fin was hemiheterocercal, with the vertebral column and body scales extending into an upper lobe equal in size and shape to the lower lobe. They also had several characteristic skeletal traits, such as a hatchet-shaped preopercle, a series of fulcra fringing the fins, a reduced number of branchiostegal rays, and a snout ornamented with tubercles.
The Timezgadiouine Formation, sometimes spelled as the Timesgadiouine Formation, is a Triassic geological formation in the Argana Basin of Morocco. It is a succession of red bed sediments spanning from the Olenekian to at least the Carnian, encompassing members T3 to T5 of the Argana Group. It is preceded by the Permian Ikakern Formation and succeeded by the Late Triassic Bigoudine Formation.
Redfieldius is an extinct genus of freshwater ray-finned fish that inhabited eastern North America during the Early Jurassic period. It contains a single species, R. gracilis, known from the Hettangian to the Sinemurian of the northeastern United States. It is the type genus and was the last surviving member of the order Redfieldiiformes, which was widespread and diverse throughout the preceding Triassic period. It is notable for representing possibly the first fossil bony fish collected from North America, with a specimen from Middletown collected in 1816 by Benjamin Silliman.
Pacorichthys is an extinct genus of palaeoniscoid ray-finned fish from Switzerland. It is currently only known from the Meride Limestone, a part of the Monte San Giorgio palaeontological Lagerstatten, located in Canton Ticino. This deposit dates to the Middle Triassic, specifically the Late Ladinian. It was a small, fusiform fish similar to a large amount of other paleonisciformes though it possessed a expanded, fixed maxillary along with its suboperculum being larger than its operculum. Though not fitting with the paleoenvironments seen in the rest of the group, a Redfieldiiform affinity has been suggested for the genus. There is only a single species in the genus being P. sangiorgii.