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Mahajangasuchids
Mahajangasuchidae is an extinct family of notosuchian crocodyliforms. It currently contains two genera, ''Mahajangasuchus'' and ''Kaprosuchus'', both of which lived during the Late Cretaceous in Gondwana. It is defined as the most inclusive clade containing ''Mahajangasuchus insignis'' but not ''Notosuchus terrestris'', '' Simosuchus clarki'', '' Araripesuchus gomesii'', '' Baurusuchus pachecoi'', '' Peirosaurus torminni'', ''Goniopholis crassidens'', '' Pholidosaurus schaumbergensis'', or ''Crocodylus niloticus''. Phylogenetically, Mahajangasuchidae is placed just outside pholidosaurids and more derived neosuchians. Defining characters of the family include fused nasals, a jaw articulation below the posterior maxillary tooth row, a deep mandibular symphysis that is oriented anterodorsally, and the formation of a hornlike posterodorsal process from the squamosal and parietal (which is much more pronounced in ''Kaprosuchus''). Phylogeny Cladogram showing the phylogenetic rel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mahajangasuchus
''Mahajangasuchus'' is an extinct genus of crocodyliform which had blunt, laterally compressed and serrated teeth. The type species, ''M. insignis'', lived during the Late Cretaceous; its fossils have been found in the Maevarano Formation in northern Madagascar. It was a fairly large predator, measuring up to long. Discovery and naming With the inception of the Mahajanga Basin Project (MBP) in 1993, led by Dr. David Krause, came a significant increase of discoveries and research into the fauna of the Maastrichtian Maevarano Formation in northern Madagascar. This included a variety of crocodylomorphs with the largest specimen being a well preserved disarticulated skeleton discovered in 1995 roughly 1 km south-east of the village of Berivotra. This skeleton, specimen ''UA 8654'', consisted of a complete left and partial right mandible, vertebrae of the cervical, dorsal, saccral and caudal regions, several ribs as well as material of the pectoral, pelvic girdle and limb bones. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kaprosuchus 2
''Kaprosuchus'' is an extinct genus of mahajangasuchid crocodyliform. It is known from a single nearly complete skull collected from the Upper Cretaceous Echkar Formation of Niger. The name means "boar crocodile" from the Greek , ''kapros'' ("boar") and , ''soukhos'' ("crocodile") in reference to its unusually large caniniform teeth which resemble those of a boar. It has been nicknamed "BoarCroc" by Paul Sereno and Hans Larsson, who first described the genus in a monograph published in ''ZooKeys'' in 2009 along with other Saharan crocodyliformes such as '' Anatosuchus'' and ''Laganosuchus''. The type species is ''K. saharicus''. Description ''Kaprosuchus'' is known from a nearly complete skull about 507 mm in length in which the lower jaw measured 603 mm long. Its total body length is estimated to be around . It possesses three sets of tusk-like caniniform teeth that project above and below the skull, one of which in the lower jaw fits into notches in the upper jaw. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kaprosuchus
''Kaprosuchus'' is an extinct genus of Mahajangasuchidae, mahajangasuchid crocodyliform. It is known from a single nearly complete skull collected from the Upper Cretaceous Echkar Formation of Niger. The name means "boar crocodile" from the Ancient Greek, Greek , ''kapros'' ("boar") and , ''soukhos'' ("crocodile") in reference to its unusually large caniniform teeth which resemble those of a boar. It has been nicknamed "BoarCroc" by Paul Sereno and Hans Larsson, who first described the genus in a monograph published in ''ZooKeys'' in 2009 along with other Saharan crocodyliformes such as ''Anatosuchus'' and ''Laganosuchus''. The type species is ''K. saharicus''. Description ''Kaprosuchus'' is known from a nearly complete skull about 507 mm in length in which the lower jaw measured 603 mm long. Its total body length is estimated to be around . It possesses three sets of tusk-like caniniform teeth that project above and below the skull, one of which in the lower jaw fits ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Notosuchia
Notosuchia is a clade of primarily Gondwanan mesoeucrocodylian Crocodylomorpha, crocodylomorphs that lived during the Jurassic and Cretaceous. Some phylogeny, phylogenies recover Sebecosuchia as a clade within Notosuchia, others as a sister group (see #Phylogeny, below); if Sebecosuchia is included within Notosuchia its existence is pushed into the Late Miocene or Zanclean, Early Pliocene, about 7 to 4.5 million years ago. Fossils have been found from South America, Africa, Asia, and Europe. Notosuchia was a clade of terrestrial crocodilians that evolved a range of feeding behaviours, including herbivory (''Chimaerasuchus''), omnivory (''Simosuchus''), and terrestrial hypercarnivory (''Baurusuchus''). It included many members with highly derived traits unusual for crocodylomorphs, including Mammal, mammal-like teeth, flexible bands of shield-like body armor similar to those of armadillos (''Armadillosuchus''), and possibly fleshy cheeks and Pig, pig-like snouts (''Notosuchus''). Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cenomanian
The Cenomanian is, in the International Commission on Stratigraphy's (ICS) geological timescale, the oldest or earliest age (geology), age of the Late Cretaceous epoch (geology), Epoch or the lowest stage (stratigraphy), stage of the Upper Cretaceous series (stratigraphy), Series. An age is a unit of geochronology; it is a unit of time; the stage is a unit in the stratigraphic column deposited during the corresponding age. Both age and stage bear the same name. As a unit of geologic time measure, the Cenomanian Age spans the time between 100.5 and 93.9 million years ago (Mya). In the geologic timescale, it is preceded by the Albian and is followed by the Turonian. The Upper Cenomanian starts around at 95 Mya. The Cenomanian is coeval with the Woodbinian of the regional timescale of the Gulf of Mexico and the early part of the Eaglefordian of the regional timescale of the East Coast of the United States. At the end of the Cenomanian, an anoxic event took place, called the Cenomani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neosuchia
Neosuchia is a clade within Mesoeucrocodylia that includes all modern extant crocodilians and their closest fossil relatives. It is defined as the most inclusive clade containing all Crocodylomorpha, crocodylomorphs more closely related to ''Crocodylus niloticus'' (the Nile Crocodile) than to ''Notosuchus terrestris''. Members of Neosuchia generally share a crocodilian-like bodyform adapted to freshwater aquatic life, as opposed to the terrestrial habits of more basal crocodylomorph groups. The earliest neosuchian is suggested to be the Early Jurassic ''Calsoyasuchus'', which lived during the Sinemurian and Pliensbachian stages in North America. It is often identified as a member of Goniopholididae, though this is disputed, and the taxon may lie outside Neosuchia, which places the earliest records of the group in the Middle Jurassic. Characteristics Members of Neosuchia have a wide diversity of skull shapes. Several groups convergently evolved elongate gharial-like skulls, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nasal Bone
The nasal bones are two small oblong bones, varying in size and form in different individuals; they are placed side by side at the middle and upper part of the face and by their junction, form the bridge of the upper one third of the nose. Each has two surfaces and four borders. Structure There is heavy variation in the structure of the nasal bones, accounting for the differences in sizes and shapes of the nose seen across different people. Angles, shapes, and configurations of both the bone and cartilage are heavily varied between individuals. Broadly, most nasal bones can be categorized as "V-shaped" or "S-shaped" but these are not scientific or medical categorizations. When viewing anatomical drawings of these bones, consider that they are unlikely to be accurate for a majority of people. The two nasal bones are joined at the midline internasal suture and make up the bridge of the nose. Surfaces The ''outer surface'' is concavo-convex from above downward, convex from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maxilla
In vertebrates, the maxilla (: maxillae ) is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The two maxillary bones are fused at the intermaxillary suture, forming the anterior nasal spine. This is similar to the mandible (lower jaw), which is also a fusion of two mandibular bones at the mandibular symphysis. The mandible is the movable part of the jaw. Anatomy Structure The maxilla is a paired bone - the two maxillae unite with each other at the intermaxillary suture. The maxilla consists of: * The body of the maxilla: pyramid-shaped; has an orbital, a nasal, an infratemporal, and a facial surface; contains the maxillary sinus. * Four processes: ** the zygomatic process ** the frontal process ** the alveolar process ** the palatine process It has three surfaces: * the anterior, posterior, medial Features of the maxilla include: * t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Squamosal
The squamosal is a skull bone found in most reptiles, amphibians, and birds. In fishes, it is also called the pterotic bone. In most tetrapods, the squamosal and quadratojugal bones form the cheek series of the skull. The bone forms an ancestral component of the dermal roof and is typically thin compared to other skull bones. The squamosal bone lies ventral to the temporal series and otic notch, and is bordered anteriorly by the postorbital. Posteriorly, the squamosal articulates with the quadrate and pterygoid bones. The squamosal is bordered anteroventrally by the jugal and ventrally by the quadratojugal. Function in reptiles In reptiles, the quadrate and articular bones of the skull articulate to form the jaw joint. The squamosal bone lies anterior to the quadrate bone. Anatomy in synapsids Non-mammalian synapsids In non-mammalian synapsids, the jaw is composed of four bony elements and referred to as a quadro-articular jaw because the joint is between the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neosuchia
Neosuchia is a clade within Mesoeucrocodylia that includes all modern extant crocodilians and their closest fossil relatives. It is defined as the most inclusive clade containing all Crocodylomorpha, crocodylomorphs more closely related to ''Crocodylus niloticus'' (the Nile Crocodile) than to ''Notosuchus terrestris''. Members of Neosuchia generally share a crocodilian-like bodyform adapted to freshwater aquatic life, as opposed to the terrestrial habits of more basal crocodylomorph groups. The earliest neosuchian is suggested to be the Early Jurassic ''Calsoyasuchus'', which lived during the Sinemurian and Pliensbachian stages in North America. It is often identified as a member of Goniopholididae, though this is disputed, and the taxon may lie outside Neosuchia, which places the earliest records of the group in the Middle Jurassic. Characteristics Members of Neosuchia have a wide diversity of skull shapes. Several groups convergently evolved elongate gharial-like skulls, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladogram
A cladogram (from Greek language, Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an Phylogenetic tree, evolutionary tree because it does not show how ancestors are related to descendants, nor does it show how much they have changed, so many differing evolutionary trees can be consistent with the same cladogram. A cladogram uses lines that branch off in different directions ending at a clade, a group of organisms with a last common ancestor. There are many shapes of cladograms but they all have lines that branch off from other lines. The lines can be traced back to where they branch off. These branching off points represent a hypothetical ancestor (not an actual entity) which can be inferred to exhibit the traits shared among the terminal taxa above it. This hypothetical ancestor might then provide clues about the order of evolution of various features, adaptation, and other e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
