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Sea Turtles
Sea turtles (superfamily Chelonioidea), sometimes called marine turtles, are reptiles of the order Testudines and of the suborder Cryptodira. The seven existing species of sea turtles are the flatback, green, hawksbill, leatherback, loggerhead, Kemp's ridley, and olive ridley. Six of the seven sea turtle species, all but the flatback, are present in U.S. waters, and are listed as endangered and/or threatened under the Endangered Species Act. They are listed as threatened with extinction globally on the IUCN Red List of Threatened Species. The flatback turtle is found only in the waters of Australia, Papua New Guinea, and Indonesia. Sea turtles can be categorized as hard-shelled ( cheloniid) or leathery-shelled ( dermochelyid).Wyneken, J. 2001. The Anatomy of Sea Turtles. U.S Department of Commerce NOAA Technical Memorandum NMFS-SEFSC-470, 1-172 pp. The only dermochelyid species of sea turtle is the leatherback. Description For each of the seven species of sea turtles, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Cretaceous
The Early Cretaceous (geochronology, geochronological name) or the Lower Cretaceous (chronostratigraphy, chronostratigraphic name) is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 143.1 Megaannum#SI prefix multipliers, Ma to 100.5 Ma. Geology Proposals for the exact age of the Barremian–Aptian boundary ranged from 126 to 117 Ma until recently (as of 2019), but based on drillholes in Svalbard the defining Anoxic event#Cretaceous, early Aptian Oceanic Anoxic Event 1a (OAE1a) was dated to 123.1±0.3 Ma, limiting the possible range for the boundary to c. 122–121 Ma. There is a possible link between this anoxic event and a series of Early Cretaceous large igneous provinces (LIP). The Ontong Java Plateau, Ontong Java-Manihiki Plateau, Manihiki-Hikurangi Plateau, Hikurangi large igneous province, emplaced in the South Pacific at c. 120 Ma, is by far the largest LIP in Earth's history. The Onto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fusiform
Fusiform (from Latin ''fusus'' ‘spindle’) means having a spindle (textiles), spindle-like shape that is wide in the middle and tapers at both ends. It is similar to the lemon (geometry), lemon-shape, but often implies a focal broadening of a structure that continues from one or both ends, such as an aneurysm on a blood vessel. Examples * Fusiform, a body shape common to many aquatic animals, characterized by being tapered at both the head and the tail * Fusiform, a classification of aneurysm * Fusiform bacteria (spindled rods, that is, fusiform bacilli), such as the Fusobacteriota * Fusiform cell (biology) * Fusiform face area, a part of the human visual system which seems to specialize in facial recognition * Fusiform gyrus, part of the temporal lobe of the brain * Fusiform muscle, where the fibres run parallel along the length of the muscle * Fusiform neuron, a spindle-shaped neuron References {{Reflist Geometric shapes See also * Streamliner, a fusiform hydro- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chelydridae
The Chelydridae is a family of turtles that has seven extinct and two extant genera. The extant genera are the snapping turtles, ''Chelydra'' and '' Macrochelys''. Both are endemic to the Western Hemisphere. The extinct genera are '' Acherontemys'', '' Chelydrops'', '' Chelydropsis'', '' Emarginachelys'', '' Macrocephalochelys'', '' Planiplastron'', and '' Protochelydra''. Fossil history The Chelydridae have a long fossil history, with extinct species reported from North America as well as all over Asia and Europe, far outside their present range. The earliest described chelydrid is '' Emarginachelys cretacea'', known from well-preserved fossils from the Maastrichtian stage of the Late Cretaceous of Montana. Another well-preserved fossil chelydrid is the Late Paleocene '' Protochelydra zangerli'' from North Dakota. The carapace of ''P. zangerli'' is higher-domed than that of the recent ''Chelydra'', a trait conjectured to be associated with the coexistence of large, turtle-eatin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pelomedusidae
:''Alternatively, "Pelomedusidae" may refer to the Pelomedusoidea. See below for details.'' Pelomedusidae is a family of freshwater turtles endemic to sub-Saharan Africa, including Madagascar, São Tomé, and the Seychelles (although this population may have been introduced by humans). They range in size from in carapace length, and are generally roundish in shape. They are unable to fully withdraw their heads into their shells, instead drawing them to the side and folding them beneath the upper edge of their shells, hence are called African side-necked turtles. The family contains two living genera, '' Pelomedusa'' and '' Pelusios''. They are distinguished from their closest relatives by a hinge in the front section of the plastron.Obst, Fritz Jürgen (1998): elomedusinae ''In:'' Cogger, H.G., & Zweifel, R.G. (eds.): ''Encyclopedia of Reptiles and Amphibians'': 112-113. San Diego: Academic Press. . Pelomedusids spends most of their time in the mud at the bottom of rivers or ... [...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] |
Bothremydids
Bothremydidae is an extinct family of side-necked turtles (Pleurodira) known from the Cretaceous and Cenozoic. They are closely related to Podocnemididae, and are amongst the most widely distributed pleurodire groups, with their fossils having been found in Africa, India, the Middle East, Europe, North America and South America. Bothremydids were aquatic turtles with a high morphological diversity, indicative of generalist, molluscivorous, piscivorous and possibly herbivorous grazing diets, with some probably capable of suction feeding. Unlike modern pleurodires, which are exclusively freshwater, bothremydids inhabited freshwater, marine and coastal environments. Their marine habits allowed bothremydids to disperse across oceanic barriers into Europe and North America during the early Late Cretaceous (Cenomanian). The youngest records of the group are indeterminate remains from Saudi Arabia and Oman, dating to the Miocene. Taxonomy The family is split into two subfamilies and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleurodire
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 t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angolachelys
''Angolachelys'' is an extinct genus of African marine turtle which existed in Angola during the Turonian stage of the Late Cretaceous. The type species is ''Angolachelys mbaxi''. The type MGUAN-PA includes skull, jaw, and postcranial fragments found in the Tadi Beds of the Itombe Formation. Phylogeny 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 s ... after Mateus ''et al.'' (2009). References Thalassochelydia Prehistoric turtle genera Turonian life Late Cretaceous reptiles of Africa Fossil taxa described in 2009 {{paleo-turtle-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plesiochelys
''Plesiochelys'' ("near turtle") is a genus of late Jurassic European and Asian turtle. The type species is ''Plesiochelys etalloni''. Fossil records have discovered ''Plesiochelys bigleri'' and ''Plesiochelys etalloni'' from the Kimmeridge Clay of England and outside the Swiss and French Jura Mountains. A recent studyEvers, S. W., & Benson, R. B. (2019). A new phylogenetic hypothesis of turtles with implications for the timing and number of evolutionary transitions to marine lifestyles in the group. ''Palaeontology'', 62(1), 93–134. placed ''Plesiochelys'' as an Angolachelonia and outside Testudines 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 Crypt .... References Sources *Gaffney, Eugene S. "A taxonomic revision of the Jurassic turtles Portlandemys and Plesiochelys. ''A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Jurassic
The Late Jurassic is the third Epoch (geology), epoch of the Jurassic Period, and it spans the geologic time scale, geologic time from 161.5 ± 1.0 to 143.1 ± 0.8 million years ago (Ma), which is preserved in Upper Jurassic stratum, strata.Owen 1987. In European lithostratigraphy, the name "Malm" indicates rocks of Late Jurassic age. In the past, ''Malm'' was also used to indicate the unit of geological time, but this usage is now discouraged to make a clear distinction between lithostratigraphic and geochronologic/chronostratigraphic units. Subdivisions The Late Jurassic is divided into three ages, which correspond with the three (faunal) stages of Upper Jurassic rock: Paleogeography During the Late Jurassic Epoch, Pangaea broke up into two supercontinents, Laurasia to the north, and Gondwana to the south. The result of this break-up was the emergence of the Atlantic Ocean, which initially was relatively narrow. Life forms This epoch is well known for many famous types of d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ancient Greek
Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek Dark Ages, Dark Ages (), the Archaic Greece, Archaic or Homeric Greek, Homeric period (), and the Classical Greece, Classical period (). Ancient Greek was the language of Homer and of fifth-century Athens, fifth-century Athenian historians, playwrights, and Ancient Greek philosophy, philosophers. It has contributed many words to English vocabulary and has been a standard subject of study in educational institutions of the Western world since the Renaissance. This article primarily contains information about the Homeric Greek, Epic and Classical periods of the language, which are the best-attested periods and considered most typical of Ancient Greek. From the Hellenistic period (), Ancient Greek was followed by Koine Greek, which is regar ... [...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] |
