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Patagorhynchus
''Patagorhynchus'' is a genus of prehistoric monotreme mammal from the Late Cretaceous (early Maastrichtian) Chorrillo Formation of Santa Cruz Province, Argentina. The genus contains a single species, ''Patagorhynchus pascuali''. The holotype, MPM-PV-23087, consists of a lower right molar attached to a fragment of the dentary. Based on comparisons with the closely related '' Obdurodon'', it is estimated to have weighed ~1.58 kg. It was collected near Rio Gallegos, Santa Cruz, Argentina in 2022 and is housed in the Museo Padre Molina. Etymology The first part of the genus name, ''Patago'', refers to Patagonia and Ancient Greek ῥύγχος (''rhúnkhos''), meaning "snout". The species name ''pascuali'' honors Argentine paleomammalogist Rosendo Pascual. Evolution ''Patagorynchus'' represents the oldest known monotreme species from South America, indicating that they had already arrived in the region by the end of the Cretaceous, and were present in Antarctica during the Lat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monotremaformes
Monotremes () are mammals of the order Monotremata. They are the only group of living mammals that lay eggs, rather than bearing live young. The extant monotreme species are the platypus and the four species of echidnas. Monotremes are typified by structural differences in their brains, jaws, digestive tract, reproductive tract, and other body parts, compared to the more common mammalian types. Although they are different from other living mammals in that they lay eggs, female monotremes are like other mammals in that they nurse their young with milk. Monotremes have been considered by some authors to be members of Australosphenida, a clade that contains extinct mammals from the Jurassic and Cretaceous of Madagascar, South America, and Australia, but this categorization is disputed and their taxonomy is under debate. All extant species of monotremes are indigenous to Australia and New Guinea, although they were also present during the Late Cretaceous and Paleocene epochs in sou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2023 In Paleomammalogy
This article records new taxa of fossil mammals of every kind binomial nomenclature, described during the year 2023, as well as other significant discoveries and events related to paleontology of mammals which occurred in 2023. Afrotherians Proboscideans Proboscidean research * Review of the systematics and evolutionary history of African proboscideans is published by William J. Sanders, Sanders (2023). * A study on the evolution of teeth of proboscideans from East Africa over the past 26 million years is published by Saarinen & Lister (2023), who find evidence of ratchet-like mode of evolution, with periods of rapid increase in hypsodonty and Molar (tooth)#Lophodont, loph count (probably related to episodes of increase of aridity) alternating with longer periods of relative stasis rather than reversal of these traits. * Choudhary ''et al.'' (2023) report the first discovery of the fossil material of a Mammutidae, mammutid (cf. ''Zygolophodon'') from the Upper Miocene deposits ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chorrillo Formation
The Chorrillo Formation, also named as Chorillo Formation, at Fossilworks.org is a Maastrichtian (Late Cretaceous Epoch, 72.1–66 million years ago) geologic Formation (geology), formation in southern Patagonia, Argentina. The formation is more than thick and underlies the Calafate Formation and rests on top of the La Irene Formation.Marenssi et al., 2003, p.406 Fossils Dinosaur remains are among the fossils that have been recovered from the formation. Fossils recovered from the formation are:Dinosaurs Ornithopods Sauropods Theropods Thyreophorans Anurans Fishes Mammals ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ornithorhynchus
The platypus (''Ornithorhynchus anatinus''), sometimes referred to as the duck-billed platypus, is a semiaquatic, egg-laying mammal endemic to eastern Australia, including Tasmania. The platypus is the sole living representative or monotypic taxon of its family Ornithorhynchidae and genus ''Ornithorhynchus'', though a number of related species appear in the fossil record. Together with the four species of echidna, it is one of the five extant species of monotremes, mammals that lay eggs instead of giving birth to live young. Like other monotremes, the platypus has a sense of electrolocation, which it uses to detect prey in cloudy water. It is one of the few species of venomous mammals, as the male platypus has a spur on the hind foot that delivers an extremely painful venom. The unusual appearance of this egg-laying, duck-billed, beaver-tailed, otter-footed mammal at first baffled European naturalists. In 1799, the first scientists to examine a preserved platypus body jud ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tachyglossus
The short-beaked echidna (''Tachyglossus aculeatus''), also called the short-nosed echidna, is one of four living species of echidna, and the only member of the genus ''Tachyglossus'', from Ancient Greek (), meaning "fast", and (), meaning "tongue". It is covered in fur and spines and has a distinctive snout and a specialised tongue, which it uses to catch its insect prey at a great speed. Like the other extant monotremes, the short-beaked echidna lays eggs; the monotremes are the only living group of mammals to do so. The short-beaked echidna has extremely strong front limbs and claws, which allow it to burrow quickly with great power. As it needs to be able to survive underground, it has a significant tolerance to high levels of carbon dioxide and low levels of oxygen. It has no weapons or fighting ability but deters predators by curling into a ball and protecting itself with its spines. It cannot sweat or deal well with heat, so it tends to avoid daytime activity in h ... [...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] |
Steropodon
''Steropodon'' is a genus of prehistoric platypus-like monotreme, or Oviparity, egg-laying mammal. It contains a single species, ''Steropodon galmani'', that lived about 100.2–96.6 million years ago during the Cretaceous period, from early to middle Cenomanian. It is one of the oldest monotremes discovered, and is one of the oldest Australian mammal discoveries. Several other monotremes are known from the Griman Creek Formation, including ''Dharragarra'', ''Kollikodon'', ''Opalios'', ''Parvopalus'', and ''Stirtodon''. Taxonomy The dentition of ''Steropodon'' is somewhat similar to that of therians—the Placentalia, placentals and the marsupials—specifically the presence of the tribosphenic molar tooth which was thought to be exclusive to therians since the Cretaceous. This, along with the tribosphenic molar discoveries of monotreme-relatives ''Ausktribosphenos'' and ''Ambondro mahabo'' of which the latter evolved in the Jurassic, led to the conclusion that the Molar (tooth), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Teinolophos
''Teinolophos'', from Ancient Greek τείνω (''teínō''), meaning "extend", and λόφος (''lóphos''), meaning "crest", is a genus of Teinolophidae, teinolophid monotreme that lived during the late Barremian Age (geology), age of the Early Cretaceous. It is known from four specimens, each consisting of a partial lower jawbone collected from the Wonthaggi Formation at Flat Rocks, Victoria (Australia), Victoria, Australia. The genus, generic name, ''Teinolophos'', means "extended ridge", a reference to its tooth structure. The species, specific name honours the artist Peter Trusler. Originally, ''Teinolophos'' was thought to be a pantotheria, eupantothere. Further research revealed similarities to ''Steropodon'', except in size: the animal was around 10 cm long. It is often listed as a Steropodontidae, steropodontid, though it may be more basal.Thomas H. Rich, James A. Hopson, Pamela G. Gill, Peter Trusler, Sally Rogers-Davidson, Steve Morton, Richard L. Cifelli, Da ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the Latin word for the white limestone known as chalk. The chalk of northern France and the white cliffs of south-eastern England date from the Cretaceous Period. Climate During the Late Cretaceous, the climate was warmer than present, although throughout the period a cooling trend is evident. The tropics became restricted to equatorial regions and northern latitudes experienced markedly more seasonal climatic conditions. Geography Due to plate tectonics, the Americas were gradually moving westward, causing the Atlantic Ocean to expand. The Western Interior Seaway divided North America into eastern and western halves; Appalachia and Laramidia. India maintained a northward course towards Asia. In the Southern Hemisphere, Aus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monotrematum
''Monotrematum sudamericanum'' is an extinct monotreme species from the Paleocene (Peligran) Salamanca Formation in Patagonia, Argentina. It is one of only two monotremes found outside Oceania. Taxonomy A species described in 1992 and assigned to a new genus ''Monotrematum'' as the type. It is currently the only known species of the genus. The authors compared their fossil material to the genus ''Obdurodon'', ornithorhynchid species first discovered at Australian fossil sites in 1975. It is considered to possibly be a Stem group, stem-ornithorhynchid, although this is uncertain given that several divergence estimates have found the family to be significantly younger. Description ''Monotrematum sudamericanum'' is known only from two lower and one upper platypus-like teeth. It is the only known non-Australasian ornithorhynchid. The main difference, apart from continent and age, is its size: the teeth of ''Monotrematum'' are around twice as large as those of other similar species in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
