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Ophiacodontids
Ophiacodontidae is an extinct family of early synapsids from the Carboniferous and Permian. ''Archaeothyris'', and ''Clepsydrops'' were among the earliest ophiacodontids, appearing in the Late Carboniferous. Ophiacodontids are among the most basal synapsids, an offshoot of the lineage which includes therapsids and their descendants, the mammals. The group became extinct by the Kungurian or the Roadian, replaced by anomodonts, theriodonts, and the diapsid reptiles. Characteristics The lifestyle of ophiacodonts has long been controversial. Some studies suggested that they were semi-aquatic, and some even suggested a fairly aquatic lifestyle, but a recent study based on a quantitative inference model suggested that both ''Clepsydrops'' and ''Ophiacodon'' were terrestrial. Vertebral morphometric data also support, though ambiguously, a rather terrestrial lifestyle for ''Ophiacodon'', which could reach a length of . ''Archaeothyris'' may also have been terrestrial, but no detailed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protoclepsydrops
''Protoclepsydrops'' is an extinct genus of early synapsids, found in Joggins, Nova Scotia. The name means 'first ''Clepsydrops, and refers to it being the predecessor of the other early synapsid ''Clepsydrops''. Description Like ''Archaeothyris'', ''Protoclepsydrops'' resembled a modern lizard in superficial appearance. However, ''Protoclepsydrops'' had primitive vertebrae with tiny neural processes typical of their amniote ancestors. ''Protoclepsydrops'' is known from a few vertebrae and some humeri. Classification Its skeletal remains indicate that it may have been more closely related to synapsids than to sauropsids, making it a possible stem-mammal. If so, it is the oldest synapsid known, though its status is unconfirmed because its remains are too fragmentary. ''Protoclepsydrops'' lived slightly earlier than ''Archaeothyris''.Benton M.J. and Donoghue P.C.J. 2006. Palaeontological evidence to date the tree of life. ''Molecular biology and evolution''. 24(1): 26–53/ref> ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Carboniferous
Late or LATE may refer to: Everyday usage * Tardy, or late, not being on time * Late (or the late) may refer to a person who is dead Music * Late (The 77s album), ''Late'' (The 77s album), 2000 * Late (Alvin Batiste album), 1993 * Late!, a pseudonym used by Dave Grohl on his ''Pocketwatch (album), Pocketwatch'' album * Late (rapper), an underground rapper from Wolverhampton * "Late", a song by Kanye West from ''Late Registration'' Other uses * Late (Tonga), an uninhabited volcanic island southwest of Vavau in the kingdom of Tonga * Late (The Handmaid's Tale), "Late" (''The Handmaid's Tale''), a television episode * LaTe, Laivateollisuus, Oy Laivateollisuus Ab, a defunct shipbuilding company * Limbic-predominant age-related TDP-43 encephalopathy, a proposed form of dementia * Local-authority trading enterprise, a New Zealand business law * Local average treatment effect, a concept in econometrics * Late, a synonym for ''cooler'' in Stellar classification#"Early" and "late" nomencla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboniferous
The Carboniferous ( ) is a Geologic time scale, geologic period and System (stratigraphy), system of the Paleozoic era (geology), era that spans 60 million years, from the end of the Devonian Period Ma (million years ago) to the beginning of the Permian Period, Ma. It is the fifth and penultimate period of the Paleozoic era and the fifth period of the Phanerozoic eon (geology), eon. In North America, the Carboniferous is often treated as two separate geological periods, the earlier Mississippian (geology), Mississippian and the later Pennsylvanian (geology), Pennsylvanian. The name ''Carboniferous'' means "coal-bearing", from the Latin ("coal") and ("bear, carry"), and refers to the many coal beds formed globally during that time. The first of the modern "system" names, it was coined by geologists William Conybeare (geologist), William Conybeare and William Phillips (geologist), William Phillips in 1822, based on a study of the British rock succession. Carboniferous is the per ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caseasauria
Caseasauria is one of the two main clades of early synapsids, the other being the Eupelycosauria. Caseasaurs are currently known only from the Late Carboniferous and the Permian, and include two superficially different families, the small insectivorous or carnivorous Eothyrididae, and the large, herbivory, herbivorous Caseidae. These two groups share a number of specialised features associated with the morphology of the snout and external nares, naris. The ancestor of caseasaurs can be traced back to an insect eating or an omnivorous reptile-like synapsid from the Pennsylvanian (geology), Pennsylvanian time of the Carboniferous, possibly resembling ''Archaeothyris'', the earliest known synapsid. The caseasaurs were abundant during the later part of the Early Permian, but by the Middle Permian caseasaur diversity declined because the group was outcompeted by the more successful therapsids. The last caseasaurs became extinct at the end of the Guadelupian (Middle Permian). Descript ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Varanids
The Varanidae are a family of lizards in the superfamily Varanoidea and order Anguimorpha. The family, a group of carnivorous and frugivorous lizards, includes the living genus '' Varanus'' and a number of extinct genera more closely related to ''Varanus'' than to the earless monitor lizard (''Lanthanotus''). ''Varanus'' includes the Komodo dragon (the largest living lizard), crocodile monitor, savannah monitor, the goannas of Australia and Southeast Asia, and various other species with a similarly distinctive appearance. Their closest living relatives are the earless monitor lizard and Chinese crocodile lizard. The oldest members of the family are known from the Late Cretaceous of Mongolia. Taxonomy The Varanidae were defined (using morphological characteristics) by Estes, de Queiroz and Gauthier (1988) as the clade containing the most recent common ancestor of ''Lanthanotus'' and ''Varanus'' and all of its descendants. A similar definition was formulated by Conrad ''et al.'' ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aquatic Animal
An aquatic animal is any animal, whether vertebrate or invertebrate, that lives in a body of water for all or most of its lifetime. Aquatic animals generally conduct gas exchange in water by extracting dissolved oxygen via specialised respiratory system, respiratory organ (biology), organs called gills, cutaneous respiration, through the skin or enteral respiration, across enteral mucosae, although some are evolution, evolved from terrestrial ancestors that re-adaptation, adapted to aquatic environments (e.g. marine reptiles and marine mammals), in which case they actually use lungs to breathing, breathe air and are essentially apnea, holding their breath when living in water. Some species of gastropod mollusc, such as the Elysia chlorotica, eastern emerald sea slug, are even capable of kleptoplastic photosynthesis via endosymbiosis with ingested yellow-green algae. Almost all aquatic animals reproduce in water, either oviparously or viviparously, and many species routinely fish ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophiacodon Mirus
''Ophiacodon'' (meaning "snake tooth") is an extinct genus of synapsid belonging to the family Ophiacodontidae that lived from the Late Carboniferous to the Early Permian in North America and Europe. The genus was named along with its type species ''O. mirus'' by paleontologist Othniel Charles Marsh in 1878 and currently includes five other species. As an ophiacodontid, ''Ophiacodon'' is one of the most basal synapsids and is close to the evolutionary line leading to mammals. Description ''Ophiacodon'' has a large skull with a deep snout. It has the longest skull of any early synapsid, reaching up to in one specimen. The jaws are lined with many small teeth. It was larger than most other tetrapods (four-limbed vertebrates) of its time, ranging from in length and in weight. Specimens of ''Ophiacodon'' vary greatly in size. These differences in size were once used to distinguish species, but are now recognized as ontogenetic variations related to the ages of individuals. Sma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diapsid
Diapsids ("two arches") are a clade of sauropsids, distinguished from more primitive eureptiles by the presence of two holes, known as temporal fenestrae, in each side of their skulls. The earliest traditionally identified diapsids, the araeoscelidians, appeared about three hundred million years ago during the late Carboniferous period. All diapsids other than the most primitive ones in the clade Araeoscelidia are often placed into the clade Neodiapsida. The diapsids are extremely diverse, and include birds and all modern reptile groups, including turtles, which were historically thought to lie outside the group. All modern reptiles and birds are placed within the neodiapsid subclade Sauria. Although some diapsids have lost either one hole (lizards), or both holes (snakes and turtles), or have a heavily restructured skull (modern birds), they are still classified as diapsids based on their ancestry. At least 17,084 species of diapsid animals are extant: 9,159 birds, and 7,925 s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theriodonts
The theriodonts (clade Theriodontia) are a major group of therapsids which appeared during the Middle Permian and which includes the gorgonopsians and the eutheriodonts, itself including the therocephalians and the cynodonts. Naming In 1876, Richard Owen named a suborder Theriodontia, which he divided into the Cynodontia and the Gomphodontia. In 1956, D. M. S. Watson and Alfred Romer divided Therapsida into Theriodontia, which predominantly included carnivorous species, and the mostly herbivorous Anomodontia, defined as comprising Dinocephalia as well as Venyukovioidea and Dicynodontia. The modern clade concept was devised by James Allen Hopson. In his system, Theriodontia fall into two main groups: the Gorgonopsia and the Eutheriodontia. The latter consist of the Therocephalia and Cynodontia.J.A. Hopson. 1999. "Therapsids". ''Encyclopedia of Paleontology'' 2: 1256-1266 Evolution Theriodonts appeared at the same time as their sister group within the Neotherapsida, the Anomodo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anomodont
Anomodontia is an extinct group of non-mammalian therapsids from the Permian and Triassic periods. By far the most speciose group are the dicynodonts, a clade of beaked, tusked herbivores. Anomodonts were very diverse during the Middle Permian, including primitive forms like '' Anomocephalus'' and '' Patranomodon'' and groups like Venyukovioidea and Dromasauria. Dicynodonts became the most successful and abundant of all herbivores in the Late Permian, filling ecological niches ranging from large browsers down to small burrowers. Few dicynodont families survived the Permian–Triassic extinction event, but one lineage ( Kannemeyeriiformes) evolved into large, stocky forms that became dominant terrestrial herbivores right until the Late Triassic, when changing conditions caused them to decline, finally going extinct during the Triassic–Jurassic extinction event. Classification Taxonomy * Order Therapsida * Suborder Anomodontia ** '' Biseridens'' ** '' Patranomodon'' ** ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roadian
In the geologic timescale, the Roadian is an age or stage of the Permian. It is the earliest or lower of three subdivisions of the Guadalupian Epoch or Series. The Roadian lasted between and million years ago (Ma). It was preceded by the Kungurian and followed by the Wordian. Stratigraphy In 1961, the regional timescale used for the southeastern US had the Wordian and Capitanian as subdivisions of the Guadalupian. Efforts to correlate the Permian stratigraphy of the southeastern US with that of Russia led to the conclusion that between the Wordian stage and the Russian Artinskian stage, another stage needed to be introduced. This stage, the Roadian Stage, was established in 1968 and took its name from the Road Canyon Formation in Brewster County, Texas, formerly considered the lower (oldest) part of the Word Formation. The stage was added to the internationally used IUGS timescale in 2001.; 1999: ''Proposal of Guadalupian and Component Roadian, Wordian and Capitanian Sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kungurian
In the geologic timescale, the Kungurian is an age or stage of the Permian. It is the latest or upper of four subdivisions of the Cisuralian Epoch or Series. The Kungurian lasted between and million years ago (Ma). It was preceded by the Artinskian and followed by the Roadian. Stratigraphy The Kungurian is named after the Russian city of Kungur in Perm Krai. The stage was introduced into scientific literature by Russian geologist Alexandr Antonovich Stukenberg (Alexander Stuckenberg) in 1890.; 2002: ''Progress report on the base of the Artinskian and base of the Kungurian by the Cisuralian Working Group'', Permophiles 41: pp 13–16. The base of the Kungurian Stage is defined as the place in the stratigraphic record where fossils of conodont species '' Neostreptognathodus pnevi'' and ''Neostreptognathodus exculptus'' first appear. As of 2009, there was no agreement yet on a global reference profile (a GSSP) for the base of the Kungurian. The top of the Kungurian (the base of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
