|
Donodontidae
Donodontidae is an extinct family of cladotherian mammals known from the Late Jurassic and Early Cretaceous of North Africa. When originally named in 1991, Donodontidae was a Monotypic taxon, monotypic family containing a single species: ''Donodon, Donodon perscriptoris''. In 2022, four more species were designated and placed within the family: ''Donodon minor'', ''Stylodens, Stylodens amerrukensis'', ''Anoualestes, Anoualestes incidens'', and ''Amazighodon, Amazighodon orbis''. All five species are Endemism, endemic to the Ksar Metlili Formation of Morocco, which is dated to the Tithonian (last stage of the Jurassic) and Berriasian (first stage of the Cretaceous). Donodontid fossils are restricted to postcanine teeth and associated jaw fragments. Teeth Donodontid molars are pre-tribosphenic, a form approaching the Tribosphenic molar, tribosphenic teeth of Theria, therian mammals and their closest relatives. The lower molars are known in ''Donodon'', ''Anoualestes'', and ''Amazi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ksar Metlili Formation
The Ksar Metlili Formation is a geological formation in eastern High Atlas of Morocco, it is late Tithonian to Berriasian in age. It is approximately thick and primarily consists of mudstone and sandstone, with thin calcareous beds. One of these calcareous beds near the middle of the sequence is an important microvertebrate locality. Subsequent to the original site, several other localities have been sampled. The depositional environment is thought to be near shore deltaic. Fossil content Fish Amphibians Lepidosaurs Turtles Choristoderes Crocodrylomorphs Pterosaurs Dinosaurs Mammals Plants References {{reflist Jurassic System of Africa Tithonian Stage Jurassic Morocco Upper Cretaceous Series of Africa Berriasian Stage Cretaceous Morocco Sandstone formations Mudstone formations Paleontology in Morocco Limestone formations Marl formations Geologic formations of Morocco ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladotheria
Cladotheria is a clade (sometimes ranked as a legion) of mammals. It contains modern therian mammals (marsupials and placentals) and several extinct groups, such as the "dryolestoids", amphitheriids and peramurids. The clade was named in 1975 by Malcolm McKenna. In 2002, it was defined as a node-based taxon containing "the common ancestor of dryolestids and living therians, plus all its descendants". A different, stem-based definition was given in 2013, in which Cladotheria contains all taxa that are closer to ''Mus musculus'' (the house mouse) than to the " symmetrodont" '' Spalacotherium tricuspidens''. Cladotheria incorporates a set of nested mammal clades culminating in Tribosphenida (also known as Boreosphenida), mammals with fully tribosphenic teeth such as therians and a few of their closest relatives. The clade Prototribosphenida includes "the common ancestor of '' Vincelestes'' and living therians, plus all of its descendants". Apart from tribosphenids, Prototrib ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Donodon
''Donodon'' is an extinct genus of mammal from the Ksar Metlili Formation of Talssint, Morocco, which has been dated to the Late Jurassic to Early Cretaceous epochs (Tithonian–Berriasian ages). The type species ''D. perscriptoris'' was described in 1991 by the palaeontologist Denise Sigogneau-Russell. A second species, ''D. minor'', was named in 2022. ''Donodon'' was a member of Cladotheria, a group that includes therian mammals (marsupials and placentals) and some of their closest relatives. It differed from dryolestids in having upper molars that were not compressed mesiodistally. Some studies have suggested that it was closely related to various South American cladotherians in the clade Meridiolestida, with specific similarities to '' Mesungulatum'', a herbivorous mesungulatid, being noted.Bonaparte, J.F. 2002. New Dryolestida (Theria) from the LateCretaceous of Los Alamitos, Argentina, and paleogeographicalcomments.Neues Jahrbuch fu ̀ˆr Geologie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protoconid
Many different terms have been proposed for features of the tooth crown in mammals. The structures within the molars receive different names according to their position and morphology. This nomenclature was developed by Henry Fairfield Osborn in 1907 and is, although with many variations, the one that continues today. Suffixes Tooth structures bear suffixes in order to note the type of structure they are and whether they are present in the upper or lower molars. * The suffix "-cones /-conids" (upper molar/lower molar) is added to the main cusps: Paracone, Metacone, Protocone and Hypocone on the upper molar, and Paraconid, Metaconid, Protoconid, Hypoconid and Entoconid on the lower molar. This name is used for both bunodont and selenodont molars, that is, as many for "buno" pillar-like cusps as for "selenes" crescent-like cusps. * The suffix "-conule /-conulid" (upper molar/lower molar) is added to the secondary cusps. For example, Metaconule, Hypoconulid. * The suffix "-style/-s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypoconulid
Many different terms have been proposed for features of the tooth crown in mammals. The structures within the molars receive different names according to their position and morphology. This nomenclature was developed by Henry Fairfield Osborn in 1907 and is, although with many variations, the one that continues today. Suffixes Tooth structures bear suffixes in order to note the type of structure they are and whether they are present in the upper or lower molars. * The suffix "-cones /-conids" (upper molar/lower molar) is added to the main cusps: Paracone, Metacone, Protocone and Hypocone on the upper molar, and Paraconid, Metaconid, Protoconid, Hypoconid and Entoconid on the lower molar. This name is used for both bunodont and selenodont molars, that is, as many for "buno" pillar-like cusps as for "selenes" crescent-like cusps. * The suffix "-conule /-conulid" (upper molar/lower molar) is added to the secondary cusps. For example, Metaconule, Hypoconulid. * The suffix "-style/-s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protocone
A cusp is a pointed, projecting, or elevated feature. In animals, it is usually used to refer to raised points on the crowns of teeth. The concept is also used with regard to the leaflets of the four heart valves. The mitral valve, which has two cusps, is also known as the bicuspid valve, and the tricuspid valve has three cusps. In humans A cusp is an occlusal or incisal eminence on a tooth. Canine teeth, otherwise known as cuspids, each possess a single cusp, while premolars, otherwise known as bicuspids, possess two each. Molars normally possess either four or five cusps. In certain populations the maxillary molars, especially first molars, will possess a fifth cusp situated on the mesiolingual cusp known as the Cusp of Carabelli. One other variation of the upper first premolar is the 'Uto-Aztecan' upper premolar. It is a bulge on the buccal cusp that is only found in Native American Indians, with highest frequencies of occurrence in Arizona. The name is not a dental ter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mortar And Pestle
A mortar and pestle is a set of two simple tools used to prepare ingredients or substances by compression (physics), crushing and shear force, grinding them into a fine Paste (rheology), paste or powder in the kitchen, laboratory, and pharmacy. The ''mortar'' () is characteristically a bowl, typically made of hardwood, metal, ceramic, or hard stone such as granite. The ''pestle'' (, also ) is a blunt, club-shaped object. The substance to be ground, which may be wet or dry, is placed in the mortar where the pestle is pounded, pressed, or rotated into the substance until the desired texture is achieved. Mortars and pestles have been used in cooking since the Stone Age; today they are typically associated with the pharmacy profession due to their historical use in preparing medicines. They are used in chemistry settings for pulverizing small amounts of chemicals; in arts and cosmetics for pulverizing pigments, binders, and other substances; in ceramics for making Grog (clay), grog; ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Talonid
The molars or molar teeth are large, flat teeth at the back of the mouth. They are more developed in mammals. They are used primarily to grind food during chewing. The name ''molar'' derives from Latin, ''molaris dens'', meaning "millstone tooth", from ''mola'', millstone and ''dens'', tooth. Molars show a great deal of diversity in size and shape across the mammal groups. The third molar of humans is sometimes vestigial. Human anatomy In humans, the molar teeth have either four or five cusps. Adult humans have 12 molars, in four groups of three at the back of the mouth. The third, rearmost molar in each group is called a wisdom tooth. It is the last tooth to appear, breaking through the front of the gum at about the age of 20, although this varies among individuals and populations, and in many cases the tooth is missing. The human mouth contains upper (maxillary) and lower (mandibular) molars. They are: maxillary first molar, maxillary second molar, maxillary third molar, man ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
