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Araripemydidae
Araripemydidae is a family of freshwater aquatic turtles belonging to the order Pleurodira (side-necked turtles), known from the Early Cretaceous of South America and Africa. The family contains two recognised monotypic genera, ''Araripemys'' and '' Taquetochelys'', from the Santana Group of Brazil and the Elrhaz Formation of Niger, respectively, which date to the Aptian-Albian stages of the Early Cretaceous. They are consider to be the most basal lineage within the Pelomedusoides The Pleurodira are one of the two living suborders of turtles, the other being the Cryptodira. The division between these two suborders represents a very deep evolutionary divide between two very different types of turtles. The physical differenc .... They are thought to have been specialised suction feeders. ''Laganemys'' was named in 2013 but was later determined to be synonymous with ''Taquetochelys.'' References Late Cretaceous first appearances Paleocene extinctions Prehistoric turtle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elrhaz Formation
The Elrhaz Formation is a geological Formation (geology), formation in Niger, West Africa. Its strata date back to the Early Cretaceous, about 125 to 112 million years ago. Dinosaur remains are among the fossils that have been recovered from the formation, alongside those of multiple species of crocodyliformes. Gadoufaoua Gadoufaoua (Tuareg language, Tuareg for "the place where camels fear to go") is a site within the Elrhaz Formation (located at ) in the Tenere desert of Niger known for its extensive fossil graveyard. It is where remains of ''Sarcosuchus imperator'', popularly known as SuperCroc, were found (by Paul Sereno in 1997, for example), including vertebrae, limb bones, armor plates, jaws, and a nearly complete skull. Gadoufaoua is very hot and dry. Based on the sedimentary and fossil record, Gadoufaoua had trees, plants, and wide rivers 112 million years ago. The river covered the remains of dead animals, the fossilized remains of which were protected by the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleurodira
The Pleurodira are one of the two living suborders of turtles, the other being the Cryptodira. The division between these two suborders represents a very deep evolutionary divide between two very different types of turtles. The physical differences between them, although anatomical and largely internal, are nonetheless significant, and the zoogeographic implications of them are substantial. The Pleurodira are known more commonly as the side-necked turtles and the name Pleurodira quite literally translates to side neck, whereas the Cryptodira are known as hidden-necked turtles. The Pleurodira turtles are currently restricted to freshwater habitats in the Southern Hemisphere, largely to Australia, South America, and Africa. Within the Pleurodira, three living families are represented: Chelidae, also known as the Austro-South American side-necked turtles, the Pelomedusidae, also known as the African mud terrapins, and the Podocnemididae, also known as the American side-neck rive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pelomedusoides
The Pleurodira are one of the two living suborders of turtles, the other being the Cryptodira. The division between these two suborders represents a very deep evolutionary divide between two very different types of turtles. The physical differences between them, although anatomical and largely internal, are nonetheless significant, and the zoogeographic implications of them are substantial. The Pleurodira are known more commonly as the side-necked turtles and the name Pleurodira quite literally translates to side neck, whereas the Cryptodira are known as hidden-necked turtles. The Pleurodira turtles are currently restricted to freshwater habitats in the Southern Hemisphere, largely to Australia, South America, and Africa. Within the Pleurodira, three living families are represented: Chelidae, also known as the Austro-South American side-necked turtles, the Pelomedusidae, also known as the African mud terrapins, and the Podocnemididae, also known as the American side-neck river turt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Araripemys
''Araripemys'' is an extinct marine turtle genus from 112 to 109 million years ago, in the Early Cretaceous Crato and Romualdo Formations of the Araripe Basin in northeastern Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population .... It is one of the oldest known pleurodires. References Pleurodira Prehistoric turtle genera Early Cretaceous turtles Albian life Prehistoric turtles of South America Early Cretaceous reptiles of South America Cretaceous Brazil Crato Formation Romualdo Formation Fossil taxa described in 1988 {{paleo-turtle-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turtle
Turtles are reptiles of the order (biology), order Testudines, characterized by a special turtle shell, shell developed mainly from their ribs. Modern turtles are divided into two major groups, the Pleurodira (side necked turtles) and Cryptodira (hidden necked turtles), which differ in the way the head retracts. There are 360 living and recently extinct species of turtles, including land-dwelling tortoises and freshwater terrapins. They are found on most continents, some islands and, in the case of sea turtles, much of the ocean. Like other Amniote, amniotes (reptiles, birds, and mammals) they breathe air and do not lay eggs underwater, although many species live in or around water. Turtle shells are made mostly of bone; the upper part is the domed Turtle shell#Carapace, carapace, while the underside is the flatter plastron or belly-plate. Its outer surface is covered in scale (anatomy), scales made of keratin, the material of hair, horns, and claws. The carapace bones deve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monotypic Taxon
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of Genus, genera, the term "unispecific" or "monospecific" is sometimes preferred. In botanical nomenclature, a monotypic genus is a genus in the special case where a genus and a single species are simultaneously described. Theoretical implications Monotypic taxa present several important theoretical challenges in biological classification. One key issue is known as "Gregg's Paradox": if a single species is the only member of multiple hierarchical levels (for example, being the only species in its genus, which is the only genus in its family), then each level needs a distinct definition to maintain logical structure. Otherwise, the different taxonomic ranks become effectively identical, which creates problems for organizing biological diversity in a hierarchical o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Santana Group
The Santana Group is a geologic group, formerly included as the middle part of the Araripe Group, in the Araripe Basin of northeastern Brazil. The group comprises the Crato, Ipubi and Romualdo Formations and is dated to the Aptian to Albian stages of the Early Cretaceous. The formations of the group were deposited in a lacustrine to subtidal shallow marine environment in the Araripe rift basin.Santana Group at .org The Santana Group has provided a rich assemblage of fossils; flora, fish, arthropods insects, turtles, snakes, dinosaurs including '' |
Aptian
The Aptian is an age (geology), age in the geologic timescale or a stage (stratigraphy), stage in the stratigraphic column. It is a subdivision of the Early Cretaceous, Early or Lower Cretaceous epoch (geology), Epoch or series (stratigraphy), Series and encompasses the time from 121.4 ± 1.0 annum, Ma to 113.0 ± 1.0 Ma (million years ago), approximately. The Aptian succeeds the Barremian and precedes the Albian, all part of the Lower/Early Cretaceous. The Aptian partly overlaps the upper part of the Western Europe, Western European Urgonian Stage. The Selli Event, also known as OAE1a, was one of two oceanic anoxic events in the Cretaceous Period, which occurred around 120 annum, Ma and lasted approximately 1 to 1.3 million years, being marked by enhanced silicate weathering, as well as ocean acidification. The Aptian extinction was a minor extinction event hypothesized to have occurred around 116 to 117 Ma. Stratigraphic definitions The Aptian was named after the small city o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albian
The Albian is both an age (geology), age of the geologic timescale and a stage (stratigraphy), stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early Cretaceous, Early/Lower Cretaceous epoch (geology), Epoch/series (stratigraphy), Series. Its approximate time range is 113.0 ± 1.0 annum, Ma to 100.5 ± 0.9 Ma (million years ago). The Albian is preceded by the Aptian and followed by the Cenomanian. Stratigraphic definitions The Albian Stage was first proposed in 1842 by Alcide d'Orbigny. It was named after Alba, the Latin name for Aube (river), River Aube in France. A Global Boundary Stratotype Section and Point (GSSP), ratified by the IUGS in 2016, defines the base of the Albian as the first occurrence of the planktonic foraminiferan ''Hedbergellidae, Microhedbergella renilaevis'' at the Col de Pré-Guittard section, Arnayon, Drôme, France. The top of the Albian Stage (the base of the Cenomanian Stage and Upper Cretaceous Series) is defined ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basal (phylogenetics)
In phylogenetics, basal is the direction of the ''base'' (or root) of a phylogenetic tree#Rooted tree, rooted phylogenetic tree or cladogram. The term may be more strictly applied only to nodes adjacent to the root, or more loosely applied to nodes regarded as being close to the root. Note that extant taxa that lie on branches connecting directly to the root are not more closely related to the root than any other extant taxa. While there must always be two or more equally "basal" clades sprouting from the root of every cladogram, those clades may differ widely in taxonomic rank, Phylogenetic diversity, species diversity, or both. If ''C'' is a basal clade within ''D'' that has the lowest rank of all basal clades within ''D'', ''C'' may be described as ''the'' basal taxon of that rank within ''D''. The concept of a 'key innovation' implies some degree of correlation between evolutionary innovation and cladogenesis, diversification. However, such a correlation does not make a given ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suction Feeder
Aquatic feeding mechanisms face a special difficulty as compared to feeding on land, because the density of water is about the same as that of the prey, so the prey tends to be pushed away when the mouth is closed. This problem was first identified by Robert McNeill Alexander. As a result, underwater predators, especially bony fish, have evolved a number of specialized feeding mechanisms, such as filter feeding, ram feeding, suction feeding, protrusion, and pivot feeding. Most underwater predators combine more than one of these basic principles. For example, a typical generalized predator, such as the cod, combines suction with some amount of protrusion and pivot feeding. Suction feeding Suction feeding is a method of ingesting a prey item in fluids by sucking the prey into the predator's mouth. It is a highly coordinated behavior achieved by the dorsal rotation of the dermatocranium, lateral expansion of the suspensorium, and the depression of the lower jaw and hyoid. Suct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
