query: taxon_rank tritheledontidae
supports: Brazil, officially the Federative Republic of Brazil, is the largest country in both South America and Latin America. As the world's fifth-largest country by both area and population, it is the largest country to have Portuguese as an official language and the only one in the Americas. Bounded by the Atlantic Ocean on the east, Brazil has a coastline of . It borders all other South American countries except Ecuador and Chile and covers 47.3% of the continent's land area. Its Amazon River basin includes a vast tropical forest, home to diverse wildlife, a variety of ecological systems, and extensive natural resources spanning numerous protected habitats. This unique environmental heritage makes Brazil one of 17 megadiverse countries, and is the subject of significant global interest and debate regarding deforestation and environmental protection. South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded on the south by of coastline of Southern Africa stretching along the South Atlantic and Indian Oceans, on the north by the neighbouring countries of Namibia, Botswana and Zimbabwe, and on the east and northeast by Mozambique and Swaziland, and surrounding the kingdom of Lesotho. South Africa is the 25th-largest country in the world by land area, and with close to 56 million people, is the world's 24th-most populous nation. It is the southernmost country on the mainland of the Old World or the Eastern Hemisphere. It is the only country that borders both the Atlantic Ocean and the Indian Ocean. About 80 percent of South Africans are of Sub-Saharan African ancestry, divided among a variety of ethnic groups speaking different Bantu languages, nine of which have official status. The remaining population consists of Africa's largest communities of European (white), Asian (Indian), and multiracial (coloured) ancestry. The TriassicJurassic extinction event marks the boundary between the Triassic and Jurassic periods, , and is one of the major extinction events of the Phanerozoic eon, profoundly affecting life on land and in the oceans. In the seas, a whole class (conodonts) and 34% of marine genera disappeared. On land, all pseudosuchians (non-ornithodiran archosaurs) other than crocodylomorphs (Sphenosuchia and Crocodyliformes), some remaining therapsids, and many of the large amphibians became extinct. South America is a continent located in the western hemisphere, mostly in the southern hemisphere, with a relatively small portion in the northern hemisphere. It is also considered a subcontinent of the Americas, which is the model used in nations that speak Romance languages. The reference to South America instead of other regions (like Latin America or the Southern Cone) has increased in the last decades due to changing geopolitical dynamics (in particular, the rise of Brazil). Theriiformes is a subclass of mammals. The term was coined in 1997 by McKenna & Bell in their classification of mammals. Theria (Greek: "", wild beast) is a subclass of mammals amongst the Theriiformes (the sister taxa to Yinotheria). Theria includes the eutherians (including the placental mammals) and the metatherians (including the marsupials). Rats are various medium-sized, long-tailed rodents of the superfamily Muroidea. "True rats" are members of the genus "Rattus", the most important of which to humans are the black rat, "Rattus rattus", and the brown rat, "Rattus norvegicus". Many members of other rodent genera and families are also referred to as rats, and share many characteristics with true rats. The Triassic is a geologic period and system which spans 50.9 million years from the end of the Permian Period million years ago (Mya), to the beginning of the Jurassic Period Mya. The Triassic is the first period of the Mesozoic Era. Both the start and end of the period are marked by major extinction events. The Triassic was named in 1834 by Friedrich von Alberti, after the three distinct rock layers ("tri" meaning "three") that are found throughout Germany and northwestern Europered beds, capped by marine limestone, followed by a series of terrestrial mud- and sandstonescalled the "Trias". Lesotho, officially the Kingdom of Lesotho, is an enclaved, landlocked country in southern Africa completely surrounded by South Africa. It is just over in size and has a population slightly over two million. Its capital and largest city is Maseru.  Synapsids (Greek, 'fused arch'), synonymous with theropsids (Greek, 'beast-face'), are a group of animals that includes mammals and every animal more closely related to mammals than to other living amniotes. They are easily separated from other amniotes by having a temporal fenestra, an opening low in the skull roof behind each eye, leaving a bony arch beneath each; this accounts for their name. Primitive synapsids are usually called pelycosaurs or pelycosaur-grade synapsids; more advanced mammal-like ones, therapsids. The non-mammalian members are described as mammal-like reptiles in classical systematics; they can also be called stem mammals or proto-mammals. Synapsids evolved from basal amniotes and are one of the two major groups of the later amniotes; the other is the sauropsids, a group that includes modern reptiles and birds. The distinctive temporal fenestra developed in the ancestral synapsid about 312 million years ago, during the Late Carboniferous period. Trithelodon was an extinct genus of cynodontian therapsid that lived during the Lower Jurassic in modern South Africa. Like cynodonts, it had many traits shared by mammals. Trithelodonts were probably insectivores, and nocturnal animals. The Early Jurassic epoch (in chronostratigraphy corresponding to the Lower Jurassic series) is the earliest of three epochs of the Jurassic period. The Early Jurassic starts immediately after the Triassic-Jurassic extinction event, 201.3 Ma (million years ago), and ends at the start of the Middle Jurassic 174.1 Ma. Latin America is a group of countries and dependencies in the Americas where Romance languages are predominant. The term originated in 19th century France as "Amérique latine" to consider French-speaking territories in the Americas (Haiti, French Guiana, Martinique, Guadeloupe, Saint Martin, Saint Barthélemy) along with the larger group of countries where Spanish and Portuguese languages prevailed. It is therefore broader than the terms Ibero-America or Hispanic Americathough it usually excludes French Canada and modern French Louisiana. Vertebrates comprise all species of animals within the subphylum Vertebrata (chordates with backbones). Vertebrates represent the overwhelming majority of the phylum Chordata, with currently about 64,000 species described. Vertebrates include the jawless fish and the jawed vertebrates, which include the cartilaginous fish (sharks and rays) and the bony fish.  The neocortex, also called the neopallium and isocortex, is the part of the mammalian brain involved in higher-order brain functions such as sensory perception, cognition, generation of motor commands, spatial reasoning and language.  Laurentia or the North American Craton is a large continental craton that forms the ancient geological core of the North American continent. Many times in its past, Laurentia has been a separate continent as it is now in the form of North America, although originally it also included the cratonic areas of Greenland and also the northwestern part of Scotland, known as the Hebridean Terrane. During other times in its past, Laurentia has been part of larger continents and supercontinents and itself consists of many smaller terranes assembled on a network of Early Proterozoic orogenic belts. Small microcontinents and oceanic islands collided with and sutured onto the ever-growing Laurentia, and together formed the stable Precambrian craton seen today. Sauropsida ("lizard faces") is a group of amniotes that includes all existing birds and reptiles as well as their fossil ancestors and other extinct relatives. Large land animals are either in this group or in its sister group, Synapsida, which includes mammals and their fossil relatives. This clade includes Parareptilia and other extinct clades. All living sauropsids are members of the sub-group Diapsida, the Parareptilia clade having died out 200 million years ago. The term originated in 1864 with Thomas Henry Huxley, who grouped birds with reptiles based on fossil evidence. In geology, a supercontinent is the assembly of most or all of Earth's continental blocks or cratons to form a single large landmass. However, the definition of a supercontinent can be ambiguous. Many earth scientists, such as P.F. Hoffman (1999), use the term "supercontinent" to mean "a clustering of nearly all continents". This definition leaves room for interpretation when labeling a continental body and is easier to apply to Precambrian times. Using the first definition provided here, Gondwana (a.k.a. Gondwanaland) is not considered a supercontinent, because the landmasses of Baltica, Laurentia and Siberia also existed at the same time but physically separate from each other. The landmass of Pangaea is the collective name describing all of these continental masses when they were in proximity to one another. This would classify Pangaea as a supercontinent. According to the definition by Rogers and Santosh (2004), a supercontinent does not exist today. Supercontinents have assembled and dispersed multiple times in the geologic past (see table). The positions of continents have been accurately determined back to the early Jurassic. However, beyond , continental positions are much less certain. In the geological timescale the Tithonian is the latest age of the Late Jurassic epoch or the uppermost stage of the Upper Jurassic series. It spans the time between 152.1 ± 4 Ma and 145.0 ± 4 Ma (million years ago). It is preceded by the Kimmeridgian and followed by the Berriasian stage (part of the Cretaceous). Therapsida is a group of synapsids that includes mammals and their ancestors. Many of the traits today seen as unique to mammals had their origin within early therapsids, including having their four limbs extend vertically beneath the body, as opposed to the sprawling posture of other reptiles. The earliest fossil attributed to Therapsida is "Tetraceratops insignis" from the Lower Permian.  The University of Glasgow (abbreviated as Glas. in post-nominals) is the fourth oldest university in the English-speaking world and one of Scotland's four ancient universities. It was founded in 1451. Along with the University of Edinburgh, the University was part of the Scottish Enlightenment during the 18th century. It is currently a member of Universitas 21, the international network of research universities, and the Russell Group. Reptiles are tetrapod (four-limbed vertebrate) animals in the class Reptilia, comprising today's turtles, crocodilians, snakes, amphisbaenians, lizards, tuatara, and their extinct relatives. The study of these traditional reptile orders, historically combined with that of modern amphibians, is called herpetology. Mammals are any vertebrates within the class Mammalia (from Latin "mamma" "breast"), a clade of endothermic amniotes distinguished from reptiles and birds by the possession of a neocortex (a region of the brain), hair, three middle ear bones and mammary glands. The sister group of mammals may be the extinct "Haldanodon." The mammals represent the only living Synapsida, which together with the Sauropsida form the Amniota clade. The mammals consist of the Yinotheria including monotrema and the Theriiformes including the theria. A mammary gland is an exocrine gland in mammals that produces milk to feed young offspring. Mammals get their name from the word "mammary". The mammary glands are arranged in organs such as the breasts in primates (for example, humans and chimpanzees), the udder in ruminants (for example, cows, goats, and deer), and the dugs of other animals (for example, dogs and cats). Lactorrhea, the occasional production of milk by the glands, can occur in any mammal, but in most mammals lactation, the production of enough milk for nursing, occurs only in phenotypic females who have gestated in recent months or years. It is directed by hormonal guidance from sex steroids. In a few mammalian species, male lactation can occur. Birds (Aves), also known as avian dinosaurs, are a group of endothermic vertebrates, characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a lightweight but strong skeleton. Birds live worldwide and range in size from the bee hummingbird to the ostrich. They rank as the class of tetrapods with the most living species, at approximately ten thousand, with more than half of these being passerines, sometimes known as perching birds or, less accurately, as songbirds. Tin is a chemical element with the symbol Sn (for ) and atomic number 50, is a post-transition metal in group 14 of the periodic table. It is obtained chiefly from the mineral cassiterite, which contains tin dioxide, SnO. Tin shows a chemical similarity to both of its neighbors in group 14, germanium and lead, and has two main oxidation states, +2 and the slightly more stable +4. Tin is the 49th most abundant element and has, with 10 stable isotopes, the largest number of stable isotopes in the periodic table, thanks to its magic number of protons. It has two main allotropes: at room temperature, the stable allotrope is -tin, a silvery-white, malleable metal, but at low temperatures it transforms into the less dense grey -tin, which has the diamond cubic structure. Metallic tin is not easily oxidized in air. The Jurassic (from Jura Mountains) is a geologic period and system that spans 56.3 million years from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period Mya. The Jurassic constitutes the middle period of the Mesozoic Era, also known as the Age of Reptiles. The start of the period is marked by the major TriassicJurassic extinction event. Two other extinction events occurred during the period: the Pliensbachian/Toarcian event in the Early Jurassic, and the Tithonian event at the end; however, neither event ranks among the "Big Five" mass extinctions. The Romance languages (sometimes called the Romanic languages, Latin languages, or Neo-Latin languages) are the modern languages that evolved from Vulgar Latin between the sixth and ninth centuries and that thus form a branch of the Italic languages within the Indo-European language family. The Bantu languages, technically the Narrow Bantu languages (as opposed to "Wide Bantu", a loosely defined categorization which includes other Bantoid languages), constitute a traditional branch of the NigerCongo languages. There are about 250 Bantu languages by the criterion of mutual intelligibility, though the distinction between language and dialect is often unclear, and "Ethnologue" counts 535 languages. Bantu languages are spoken largely east and south of present-day Cameroon, that is, in the regions commonly known as Central Africa, Southeast Africa, and Southern Africa. Parts of the Bantu area include languages from other language families (see map). Swaziland, officially the Kingdom of Swaziland (or ; Swazi: "Umbuso weSwatini"; sometimes called kaNgwane or Eswatini), is a sovereign state in Southern Africa. It is neighboured by Mozambique to its northeast and by South Africa to its north, west and south. The country and its people take their names from Mswati II, the 19th-century king under whose rule Swazi territory was expanded and unified. The Tritheledontidae or tritheledontids , also known as ictidosaurs , were small to medium - sized ( about 10 or 20 cm long ) cynodonts . They were extremely mammal - like , highly specialized cynodonts , although they still retained a very few reptilian anatomical traits . Tritheledontids were mainly carnivorous or insectivorous , though some species may have developed omnivorous traits . Their skeletons show that they had a close relationship to mammals . Tritheledontids or their closest relatives may have given rise to primitive mammals . The tritheledontids were one of the longest lived non-mammalian therapsid lineages , living from late Triassic to the Jurassic period . Tritheledontids became extinct in the Jurassic period , possibly due to competition with prehistoric mammals such as the triconodonts . They are known from finds in South America and South Africa , indicating that they may have lived only on the supercontinent of Gondwana . The family Tritheledontidae was named by South African paleontologist Robert Broom in 1912 . The family is often misspelled `` Trithelodontidae '' . It is possible that Tritheledontidae had vibrissae , according to the PBS documentary , Your Inner Fish . A common ancestor of all therian mammals did so . It is possible that the development of the whisker sensory system played an important role in mammalian development , more generally . In biology and ecology, extinction is the end of an organism or of a group of organisms (taxon), normally a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point. Because a species' potential range may be very large, determining this moment is difficult, and is usually done retrospectively. This difficulty leads to phenomena such as Lazarus taxa, where a species presumed extinct abruptly "reappears" (typically in the fossil record) after a period of apparent absence. A clade (from , "klados", "branch") is a group of organisms that consists of a common ancestor and all its lineal descendants, and represents a single "branch" on the "tree of life". Robert Broom FRS FRSE (30 November 1866, Paisley  6 April 1951) was a Scottish South African doctor and paleontologist. He qualified as a medical practitioner in 1895 and received his DSc in 1905 from the University of Glasgow.
candidates: branch class form genus group kingdom order series species subclass superfamily variety
answer: genus