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Sea Turtle
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 sea turtles. All six of the sea turtle species present in US waters (all of those listed above except the flatback) are listed as endangered and/or threatened under the Endangered Species Act. The seventh sea turtle species is the flatback, which exists in the waters of Australia, Papua New Guinea and Indonesia. Sea turtles can be separated into the categories of hard-shelled (cheloniid) and 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. There is only one dermochelyid species which is the leatherback sea turtle. Description For each of the seven types of sea turtles, females and males are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kemp's Ridley Sea Turtle
Kemp's ridley sea turtle (''Lepidochelys kempii''), also called the Atlantic ridley sea turtle, is the rarest species of sea turtle and is the world's most endangered species of sea turtle. It is one of two living species in the genus '' Lepidochelys'' (the other one being ''L. olivacea'', the olive ridley sea turtle). Taxonomy This species of turtle is called Kemp's ridley because Richard Moore Kemp (1825–1908) of Key West was the first to send a specimen to Samuel Garman at Harvard, but the origin of the name "ridley" itself is unknown. Prior to the term being popularly used (for both species in the genus), ''L. kempii'' at least was known as the "bastard turtle". At least one source also refers to Kemp's ridley as a "heartbreak turtle". In her book ''The Great Ridley Rescue'', Pamela Philips claimed the name was coined by fishermen who witnessed the turtles dying after being "turned turtle" (on their backs). The fishermen said the turtles "died of a broken heart". Descri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Green Sea Turtle
The green sea turtle (''Chelonia mydas''), also known as the green turtle, black (sea) turtle or Pacific green turtle, is a species of large sea turtle of the family Cheloniidae. It is the only species in the genus ''Chelonia''. Its range extends throughout tropical and subtropical seas around the world, with two distinct populations in the Atlantic and Pacific Oceans, but it is also found in the Indian Ocean. The common name refers to the usually green fat found beneath its carapace, not to the color of its carapace, which is olive to black. The dorsoventrally flattened body of ''C. mydas'' is covered by a large, teardrop-shaped carapace; it has a pair of large, paddle-like flippers. It is usually lightly colored, although in the eastern Pacific populations, parts of the carapace can be almost black. Unlike other members of its family, such as the hawksbill sea turtle, ''C. mydas'' is mostly herbivorous. The adults usually inhabit shallow lagoons, feeding mostly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loggerhead Sea Turtle
The loggerhead sea turtle (''Caretta caretta'') is a species of oceanic turtle distributed throughout the world. It is a marine reptile, belonging to the family Cheloniidae. The average loggerhead measures around in carapace length when fully grown. The adult loggerhead sea turtle weighs approximately , with the largest specimens weighing in at more than . The skin ranges from yellow to brown in color, and the shell is typically reddish brown. No external differences in sex are seen until the turtle becomes an adult, the most obvious difference being the adult males have thicker tails and shorter plastrons (lower shells) than the females. The loggerhead sea turtle is found in the Atlantic, Pacific, and Indian Oceans, as well as the Mediterranean Sea. It spends most of its life in saltwater and estuarine habitats, with females briefly coming ashore to lay eggs. The loggerhead sea turtle has a low reproductive rate; females lay an average of four egg clutches and then bec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Cretaceous
The Early Cretaceous (geochronological name) or the Lower Cretaceous ( chronostratigraphic name), is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 145 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 early Aptian Oceanic Anoxic Event 1a (OAE1a) was carbon isotope 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- Manihiki- Hikurangi large igneous province, emplaced in the South Pacific at c. 120 Ma, is by far the largest LIP in Earth's history. The Ontong Java Plateau today covers an area of 1,860,000 km2. In the Indian Ocean another LIP began to form at c. 120 Ma, the Kergue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plesiochelys
''Plesiochelys'' 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 an order of reptiles known as Testudines, characterized by a special shell developed mainly from their ribs. Modern turtles are divided into two major groups, the Pleurodira (side necked turtles) and Cryptodira (hidden necked .... References Sources *Gaffney, Eugene S. "A taxonomic revision of the Jurassic turtles Portlandemys and Plesiochelys. ''American Museum N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turtle
Turtles are an order of reptiles known as Testudines, characterized by a special 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 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 carapace, while the underside is the flatter plastron or belly-plate. Its outer surface is covered in scales made of keratin, the material of hair, horns, and claws. The carapace bones develop from ribs that grow sideways and develop into broad flat ... [...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 ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic period (), and the Classical period (). Ancient Greek was the language of Homer and of fifth-century Athenian historians, playwrights, and 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 Epic and Classical periods of the language. From the Hellenistic period (), Ancient Greek was followed by Koine Greek, which is regarded as a separate historical stage, although its earliest form closely resembles Attic Greek and its latest form approaches Medieval Greek. There were several regional dialects of Ancient Greek, of which Attic Greek developed into Koi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Jurassic
The Late Jurassic is the third epoch of the Jurassic Period, and it spans the geologic time from 163.5 ± 1.0 to 145.0 ± 0.8 million years ago (Ma), which is preserved in Upper Jurassic 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 spawning of the Atlantic Ocean. However, at this time, the Atlantic Ocean was relatively narrow. Life forms of the epoch This epoch is well known for many famous types of din ... [...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 eucryptodiran turtle which existed in Angola , national_anthem = "Angola Avante"() , image_map = , map_caption = , capital = Luanda , religion = , religion_year = 2020 , religion_ref = , coordina ... 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 after Mateus ''et al.'' (2009). References Cryptodira Prehistoric turtle genera Turonian life Late Cretaceous reptiles of Africa Fossils of Angola, Fossil taxa described in 2009 {{paleo-turtle-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metre
The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its prefixed forms are also used relatively frequently. The metre was originally defined in 1793 as one ten-millionth of the distance from the equator to the North Pole along a great circle, so the Earth's circumference is approximately km. In 1799, the metre was redefined in terms of a prototype metre bar (the actual bar used was changed in 1889). In 1960, the metre was redefined in terms of a certain number of wavelengths of a certain emission line of krypton-86. The current definition was adopted in 1983 and modified slightly in 2002 to clarify that the metre is a measure of proper length. From 1983 until 2019, the metre was formally defined as the length of the path travelled by light in a vacuum in of a second. After the 2019 ... [...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, and piscivorous diets. Unlike modern pleurodires, which are exclusively freshwater, bothremydids inhabited freshwater, marine and coastal settings. 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 a number of tribes. Bothremydidae *'' Pleurochayah appalachius'' Adrian et al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
