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Pseudotherium
''Pseudotherium'' ("false beast") is an extinct genus of mammaliamorph cynodonts from the Late Triassic of Argentina. It contains one species, ''P. argentinus'', which was first described in 2019 from remains found in the La Peña Member of the Ischigualasto Formation in the Ischigualasto-Villa Unión Basin. Discovery and naming The holotype and only known specimen, PVSJ 882, was discovered in 2006 by Argentine palaeontologist Ricardo N. Martínez during an expedition to the Ischigualasto Formation. It consists of a partial skull lacking the lower jaw, quadrate bones and most of the zygomatic arches and premaxillae. The generic epithet ''Pseudotherium'' is derived from the Greek words , meaning "false", and , meaning "beast". The specific name ''argentinus'' references the country of Argentina where it was found. Description ''Pseudotherium'' would have been a relatively large cynodont; excluding its missing premaxillae, the holotype skull is in length. Running along the top of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammaliamorph
Mammaliamorpha is a clade of cynodonts. It contains the clades Tritylodontidae and Mammaliaformes, as well as a few genera that do not belong to either of these groups. The family Tritheledontidae has also been placed in Mammaliamorpha by some phylogenetic analyses, but has been recovered outside the clade by others. According to a 2022 study based on inner ear anatomy, Mammaliamorpha may be the clade in which endothermy ("warm-bloodedness") first appeared in the mammalian lineage. Classification Mammaliamorpha was named in 1988 by the American palaeontologist Timothy B. Rowe, who defined it as comprising "the last common ancestor of Tritylodontidae and Mammalia, and all its descendants". The cladogram below is adapted from the 2019 description of the mammaliamorph ''Pseudotherium ''Pseudotherium'' ("false beast") is an extinct genus of mammaliamorph cynodonts from the Late Triassic of Argentina. It contains one species, ''P. argentinus'', which was first described in 2019 f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammaliamorpha
Mammaliamorpha is a clade of cynodonts. It contains the clades Tritylodontidae and Mammaliaformes, as well as a few genera that do not belong to either of these groups. The family Tritheledontidae has also been placed in Mammaliamorpha by some phylogenetic analyses, but has been recovered outside the clade by others. According to a 2022 study based on inner ear anatomy, Mammaliamorpha may be the clade in which endothermy ("warm-bloodedness") first appeared in the mammalian lineage. Classification Mammaliamorpha was named in 1988 by the American palaeontologist Timothy B. Rowe, who defined it as comprising "the last common ancestor of Tritylodontidae and Mammalia, and all its descendants". The cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to d ... below is adapted from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ischigualasto Formation
The Ischigualasto Formation is a Late Triassic fossiliferous formation and Lagerstätte in the Ischigualasto-Villa Unión Basin of the southwestern La Rioja Province and northeastern San Juan Province in northwestern Argentina. The formation dates to the Carnian and Norian ages and ranges between 231.7 and 225 Ma, based on ash bed dating. The up to thick formation is part of the Agua de la Peña Group, overlies Los Rastros Formation and is overlain by Los Colorados Formation. The formation is subdivided into four members, from old to young; La Peña, Cancha de Bochas, Valle de la Luna and Quebrada de la Sal. The sandstones, mudstones, conglomerates and tuffs of the formation were deposited in a humid alluvial to fluvial floodplain environment, characterized by strongly seasonal rainfall. The Ischigualasto Formation is an important paleontological unit and considered a Lagerstätte, as it preserves several genera of early dinosaurs, other archosaurs, synapsids, and temnospon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2019 In Paleontology
Flora Plants Fungi Paleomycological research * Fossil sporocarps indistinguishable from sporocarps of members of the extant genus ''Stemonitis'' are described from the Cretaceous amber from Myanmar by Rikkinen, Grimaldi & Schmidt (2019). * A study on the impact of major historical events such as the Cretaceous–Paleogene extinction event on the evolution of two major subclasses of lichen-forming fungi ( Lecanoromycetidae and Ostropomycetidae) is published by Huang ''et al.'' (2019). * Description of crustose lichens from European Paleogene amber is published by Kaasalainen ''et al.'' (2019). * Fungi belonging to the genera '' Periconia'', ''Penicillium'' and ''Scopulariopsis'', representing the first and the oldest known fossil record of these taxa, are described from the Eocene Baltic amber by Tischer ''et al.'' (2019). Sponges Research * Sponge spicules and spicule-like structures that probably represent sponge fossils are described from four sections of the Ediacaran-Ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brasilodontidae
''Brasilodon'' ("tooth from Brazil") is an extinct genus of small, mammal-like cynodonts that lived in what is now Brazil during the Norian age of the Late Triassic epoch, about 225.42 million years ago. While no complete skeletons have been found, the length of ''Brasilodon'' has been estimated at around . Its dentition shows that it was most likely an insectivore. The genus is monotypic, containing only the species ''B. quadrangularis''. ''Brasilodon'' belongs to the family Brasilodontidae, whose members were some of the closest relatives of mammals, the only cynodonts alive today. Two other brasilodontid genera, ''Brasilitherium'' and ''Minicynodon'', are now considered to be junior synonyms of ''Brasilodon''. Discovery and naming The first three specimens referred to ''Brasilodon quadrangularis'' were found at the Linha São Luiz site, a quarry near the town of Faxinal do Soturno in the state of Rio Grande do Sul. The rocks where ''Brasilodon'' was found belong to the upp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brasilodontid
''Brasilodon'' ("tooth from Brazil") is an extinct genus of small, mammal-like cynodonts that lived in what is now Brazil during the Norian age of the Late Triassic epoch, about 225.42 million years ago. While no complete skeletons have been found, the length of ''Brasilodon'' has been estimated at around . Its dentition shows that it was most likely an insectivore. The genus is monotypic, containing only the species ''B. quadrangularis''. ''Brasilodon'' belongs to the family Brasilodontidae, whose members were some of the closest relatives of mammals, the only cynodonts alive today. Two other brasilodontid genera, ''Brasilitherium'' and ''Minicynodon'', are now considered to be junior synonyms of ''Brasilodon''. Discovery and naming The first three specimens referred to ''Brasilodon quadrangularis'' were found at the Linha São Luiz site, a quarry near the town of Faxinal do Soturno in the state of Rio Grande do Sul. The rocks where ''Brasilodon'' was found belong to the uppe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Probainognathia
Probainognathia is one of the two major subgroups of the clade Eucynodontia, the other being Cynognathia. The earliest forms were carnivorous and insectivorous, though some groups eventually also evolved herbivorous diets. The earliest and most basal probainognathian is the Middle Triassic (Anisian) aged ''Lumkuia'', from South Africa, though probainognathians would not become prominent until the mid Norian stage of the Late Triassic. Three groups survived the extinction at the end of Triassic: Tritheledontidae and Tritylodontidae, which both survived until the Jurassic—the latter even into the Cretaceous (''Montirictus'' and '' Xenocretosuchus'')—and Mammaliaformes, which includes the mammals. Phylogeny Below is a cladogram from Ruta, Botha-Brink, Mitchell and Benton (2013) showing one hypothesis of cynodont relationships: See also * Evolution of mammals * List of prehistoric mammals This is an incomplete list of prehistoric mammals. It does not include extant mam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Botucaraitherium
''Botucaraitherium'' is an extinct genus of prozostrodontian cynodonts from the Late Carnian ''Riograndia'' Assemblage Zone in the Candelária Formation of the Paraná Basin in southeastern Brazil. It is known from a single type species, ''Botucaraitherium belarminoi''. The genus name is derived from the Botucaraí Hill, which dominates the landscape of Candelária, Rio Grande do Sul.Soares et al., 2014, p.1677 The species epithet An epithet (, ), also byname, is a descriptive term (word or phrase) known for accompanying or occurring in place of a name and having entered common usage. It has various shades of meaning when applied to seemingly real or fictitious people, di ... honors Belarmino Stefanello, a volunteer at the Museu Municipal Aristides Carlos Rodrigues, who found the fossil.Soares et al., 2014, p.1678 References Bibliography * Prehistoric prozostrodonts Prehistoric cynodont genera Carnian genera Late Triassic synapsids of South America Trias ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tritylodontid
Tritylodontidae ("three-knob teeth", named after the shape of their cheek teeth) is an extinct family of small to medium-sized, highly specialized mammal-like cynodonts, bearing several mammalian traits like erect limbs, endothermy and details of the skeleton. They were the last-known family of the non-mammaliaform synapsids, persisting into the Early Cretaceous. Most tritylodontids are thought to have been herbivorous, feeding on vegetation, such as stems, leaves, and roots, although at least one may have had a more omnivorous diet. Tritylodontid fossils are found in the Americas, South Africa, and Eurasia—they appear to have had an almost global distribution, including Antarctica. Description The skull of tritylodontids had a high sagittal crest. They retained the primitive condition of the joint between the quadrate bone of the skull and the articular bone of the lower jaw—the retention of the joint is one of the reasons they are technically regarded to not be mammals, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammaliaform
Mammaliaformes ("mammalian forms") is a clade that contains the crown group mammals and their closest extinct relatives; the group radiated from earlier probainognathian cynodonts. It is defined as the clade originating from the most recent common ancestor of Morganucodonta and the crown group mammals; the latter is the clade originating with the most recent common ancestor of extant Monotremata, Marsupialia, and Placentalia. Besides Morganucodonta and the crown group mammals, Mammaliaformes includes Docodonta and '' Hadrocodium'' as well as the Triassic ''Tikitherium'', the earliest known member of the group. Mammaliaformes is a term of phylogenetic nomenclature. In contrast, the assignment of organisms to Mammalia has traditionally been founded on traits and, on this basis, Mammalia is slightly more inclusive than Mammaliaformes. In particular, trait-based taxonomy generally includes ''Adelobasileus'' and ''Sinoconodon'' in Mammalia, though they fall outside the Mammaliaform ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carnian
The Carnian (less commonly, Karnian) is the lowermost stage of the Upper Triassic Series (or earliest age of the Late Triassic Epoch). It lasted from 237 to 227 million years ago (Ma). The Carnian is preceded by the Ladinian and is followed by the Norian. Its boundaries are not characterized by major extinctions or biotic turnovers, but a climatic event (known as the Carnian pluvial episode characterized by substantial rainfall) occurred during the Carnian and seems to be associated with important extinctions or biotic radiations. Stratigraphic definitions The Carnian was named in 1869 by Mojsisovics. It is unclear if it was named after the Carnic Alps or after the Austrian region of Carinthia (''Kärnten'' in German) or after the Carnia historical region in northwestern Italy. The name, however, was first used referring to a part of the Hallstatt Limestone cropping out in Austria. The base of the Carnian Stage is defined as the place in the stratigraphic record where t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Probainognathus
''Probainognathus'' meaning “progressive jaw” is an extinct genus of cynodonts that lived around 235 to 221.5 million years ago, during the Late Triassic in what is now South America. ''Probainognathus'' is a member of the family Probainognathidae, and is a close relative of the family Chiniquodontidae.Fossilworks: Gateway to the Paleobiology Database. Probainognathus Romer 1970 (therapsid). PaleoDB taxon number: 39225 , http://www.fossilworks.org/cgi-bin/bridge.pl?a=taxonInfo&taxon_no=80895 The various similarities to Chiniquodontidae led Alfred Romer to initially suggest ''Probainognathus'' be placed within that family, but it was subsequently decided that the differences were enough to warrant its placement within Probainognathidae.Romer, A.S. 1973. The Chanares (Argentina) Triassic reptile fauna. XVIII. Probelesodon minor, a new species of carnivorous cynodont; family Probainognathidae nov. Breviora, 401:1-4 ''Probainognathus jenseni'' was a species of small, carnivorous ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
