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Selmasaurus
''Selmasaurus'' is an extinct genus of marine lizard belonging to the mosasaur family. It is classified as part of the Plioplatecarpinae subfamily alongside genera like ''Angolasaurus'' and ''Platecarpus''. Two species are known, ''S. russelli'' and ''S. johnsoni''; both are exclusively known from Santonian deposits in the United States. ''Selmasaurus'' is unique among the mosasaurs in that its skull is unusually akinetic, meaning that it is incapable of widening to swallow larger prey. Most mosasaurs have skulls which possess "coupled kinesis" (mesokinesis and streptostyly), that is, parts of the jaw can open widely to accommodate large prey. Description ''Selmasaurus'' was a small predatory mosasaur at approximately 3–5 meters in length. It possesses a relatively low number of teeth for a mosasaur, the lowest of any known species at the time of its discovery. Originally classified as a plioplatecarpine mosasaur, it differs from all other plioplatecarpine mosasaurs in severa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2008 In Paleontology
Protozoa New taxa Plants Angiosperms Monocots Arthropoda Arachnids Insects Xiphosurans Fishes Bony fish Placoderms General research *Hilton & Grande redescribe the fossil mooneyes of western North America synonymizing the genus ''Eohiodon'' with ''Hiodon''. *Cicimurri, Paris, & Everhart describe a partial dentition from a Holocephali chimaeroid fish found in the Niobrara Chalk. Amphibians Jenkins, F. A., jr, Shubin, N. H., Gatesy, S. M., and Warren, A., 2008, Gerrothorax pulcherrimus from the Upper Triassic Fleming Fjord Formation of East Greenland and a reassessment of head lifting in temnospondyl feeding: Journal of Vertebrate Paleontology, v. 28, n. 4, p. 935-950. Newly named amphibians Archosaurs Newly named pseudosuchians Newly named pterosaurs Dinosaurs * Oviraptorosaurian eggs with embryonic skeletons are discovered for the first time in China. * Mongolian Late Jurassic theropod fossils are found for the first time. * A new study on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plioplatecarpinae
Plioplatecarpinae is a subfamily of mosasaurs, a diverse group of Late Cretaceous marine squamates. Members of the subfamily are informally and collectively known as "plioplatecarpines" and have been recovered from all continents, though the occurrences in Australia remain questionable. The subfamily includes the genera '' Latoplatecarpus'', ''Platecarpus'', '' Plioplatecarpus'' and ''Plesioplatecarpus''. Plioplatecarpines were small to medium-sized mosasaurs that were comparatively fast and agile compared to mosasaurs of other subfamilies. The first plioplatecarpines appear in the Turonian and are among the oldest of mosasaurs, and the clade persists throughout the Maastrichtian, a period of approximately 24 million years. The subfamily was seemingly heavily affected during a poorly understood middle-Campanian mosasaur extinction event and its genera appear to have faced competition from mosasaurine mosasaurs during the Maastrichtian, leading to a decline in numbers and in diver ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mooreville Chalk Formation
The Mooreville Chalk is a geological formation in North America, within the U.S. states of Alabama and Mississippi, which were part of the subcontinent of Appalachia. The strata date back to the early Santonian to the early Campanian stage of the Late Cretaceous. The chalk was formed by pelagic sediments deposited along the eastern edge of the Mississippi embayment. It is a unit of the Selma Group and consists of the upper Arcola Limestone Member and an unnamed lower member. Dinosaur, mosasaur, and primitive bird remains are among the fossils that have been recovered from the Mooreville Chalk Formation.Weishampel, David B; et al. (2004). "Dinosaur distribution (Late Cretaceous, North America)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 574-588. . Fish Cartilaginous fish Bony fish Reptiles Dinosaurs Indeterminate hadrosaurid, nodosaurid, dinosaur egg, and ornithomimosaur fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Platecarpus
''Platecarpus'' ("flat wrist") is an extinct genus of aquatic lizards belonging to the mosasaur family, living around 84–81 million years ago during the middle Santonian to early Campanian, of the Late Cretaceous period. Fossils have been found in the United States and possible specimens in Belgium and Africa. A well-preserved specimen of ''Platecarpus'' shows that it fed on moderate-sized fish, and it has been hypothesized to have fed on squid, and ammonites as well. Like other mosasaurs, it was initially thought to have swum in an eel-like fashion, although another study suggests that it swam more like modern sharks. An exceptionally well-preserved specimen of ''P. tympaniticus'' known as LACM 128319 shows skin impressions, pigments around the nostrils, bronchial tubes, and the presence of a high-profile tail fluke, showing that it and other mosasaurs did not necessarily have an eel-like swimming method, but were more powerful, fast swimmers. It is held in the Natural Histo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angolasaurus
''Angolasaurus'' ("Angola lizard") is an extinct genus of mosasaur. Definite remains from this genus have been recovered from the Turonian and Coniacian of Angola, and possibly the Coniacian of the United States, the Turonian of Brazil, and the Maastrichtian of Niger. While at one point considered a species of ''Platecarpus'', recent phylogenetic analyses have placed it between the (then) plioplatecarpines '' Ectenosaurus'' and '' Selmasaurus'', maintaining a basal position within the plioplatecarpinae. Its wide geographic range make it the one of the only Turonian mosasaurs with a transatlantic range. Description ''Angolasaurus'' was a small mosasaur, with a total length of about 4 meters (13 feet). It shared much of a body plan with its relative ''Platecarpus'', but with a slightly longer skull relative to body length. Its skull housed 11 maxillary teeth, 4 premaxillary teeth, and 12 dentary teeth. The phylogenetic relationship of ''Angolasaurus'' indicates that individuals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mosasaur
Mosasaurs (from Latin ''Mosa'' meaning the 'Meuse', and Ancient Greek, Greek ' meaning 'lizard') comprise a group of extinct, large marine reptiles from the Late Cretaceous. Their first fossil remains were discovered in a limestone quarry at Maastricht on the Meuse in 1764. They belong to the order Squamata, which includes lizards and snakes. Mosasaurs probably evolved from an extinct group of aquatic lizards known as Aigialosauridae, aigialosaurs in the Late Cretaceous, Earliest Late Cretaceous with 42 described genera. During the last 20 million years of the Cretaceous period (Turonian–Maastrichtian ages), with the extinction of the ichthyosaurs and Pliosauridae, pliosaurs, mosasaurs became the dominant marine predators. They themselves became extinct as a result of the Cretaceous–Paleogene extinction event, K-Pg event at the end of the Cretaceous period, about 66 million years ago. Description Mosasaurs breathed air, were powerful swimmers, and were well-adapted to livi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alabama
(We dare defend our rights) , anthem = " Alabama" , image_map = Alabama in United States.svg , seat = Montgomery , LargestCity = Huntsville , LargestCounty = Baldwin County , LargestMetro = Greater Birmingham , area_total_km2 = 135,765 , area_total_sq_mi = 52,419 , area_land_km2 = 131,426 , area_land_sq_mi = 50,744 , area_water_km2 = 4,338 , area_water_sq_mi = 1,675 , area_water_percent = 3.2 , area_rank = 30th , length_km = 531 , length_mi = 330 , width_km = 305 , width_mi = 190 , Latitude = 30°11' N to 35° N , Longitude = 84°53' W to 88°28' W , elevation_m = 150 , elevation_ft = 500 , elevation_max_m = 735.5 , elevation_max_ft = 2,413 , elevation_max_point = Mount Cheaha , elevation_min_m = 0 , elevation_min_ft = 0 , elevation_min_point = Gulf of Mexico , OfficialLang = English , Languages = * English 95.1% * Spanish 3.1% , population_demonyms = Alabamian (We dare defend our rights) , anthem = "Alabama (state song), Alabama" , i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stratigraphic
Stratigraphy is a branch of geology concerned with the study of rock layers ( strata) and layering (stratification). It is primarily used in the study of sedimentary and layered volcanic rocks. Stratigraphy has three related subfields: lithostratigraphy (lithologic stratigraphy), biostratigraphy (biologic stratigraphy), and chronostratigraphy (stratigraphy by age). Historical development Catholic priest Nicholas Steno established the theoretical basis for stratigraphy when he introduced the law of superposition, the principle of original horizontality and the principle of lateral continuity in a 1669 work on the fossilization of organic remains in layers of sediment. The first practical large-scale application of stratigraphy was by William Smith in the 1790s and early 19th century. Known as the "Father of English geology", Smith recognized the significance of strata or rock layering and the importance of fossil markers for correlating strata; he created the first geol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caitlín R
Caitlin () is a female given name of Irish origin. Historically, the Irish name Caitlín was anglicized as Cathleen or Kathleen. In the 1970s, however, non-Irish speakers began pronouncing the name according to English spelling rules as , which led to many variations in spelling such as Caitlin, Catelynn, Caitlyn, Katlyn, Kaitlin, Kaitlyn, Katelyn and Katelynn. It is the Irish version of the Old French name ''Cateline'' , which comes from Catherine, which in turn comes from the Ancient Greek Αἰκατερίνη (Aikaterine). Catherine is attributed to St. Catherine of Alexandria. Along with the many other variants of Catherine, it is generally believed to mean "pure" because of its long association with the Greek adjective καθαρός ''katharos'' (pure), though the name did not evolve from this word. Notable people Literature * Caitlin Brennan, pseudonym of Judith Tarr, American fantasy writer * Cait Brennan, American screenwriter and performer * Caitlin Davies, En ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanoplankton
Plankton are the diverse collection of organisms found in water (or air) that are unable to propel themselves against a current (or wind). The individual organisms constituting plankton are called plankters. In the ocean, they provide a crucial source of food to many small and large aquatic organisms, such as bivalves, fish and whales. Marine plankton include bacteria, archaea, algae, protozoa and drifting or floating animals that inhabit the saltwater of oceans and the brackish waters of estuaries. Freshwater plankton are similar to marine plankton, but are found in the freshwaters of lakes and rivers. Plankton are usually thought of as inhabiting water, but there are also airborne versions, the aeroplankton, that live part of their lives drifting in the atmosphere. These include plant spores, pollen and wind-scattered seeds, as well as microorganisms swept into the air from terrestrial dust storms and oceanic plankton swept into the air by sea spray. Though many plank ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the younger 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, Australia a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selma Group
The Selma Group is a geological formation in North America, within the U.S. states of Alabama, Mississippi, and Tennessee. The strata date from the Santonian to the Maastrichtian stages of the Late Cretaceous. The group is composed of, in ascending order, the Mooreville Chalk Formation, Demopolis Chalk Formation, Ripley Formation, and Prairie Bluff Chalk Formation. Dinosaur and mosasaur remains are among the fossils that have been recovered from the Selma Group.Weishampel, David B; et al. (2004). "Dinosaur distribution (Late Cretaceous, North America)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 574-588. . Oil was discovered in 1939 within the Late Cretaceous Woodruff Sandstone within the Selma Chalk Formation. Known as Mississippi's first oil field, the Tinsley Oil Field is located adjacent to Tinsley, Mississippi. See also * List of dinosaur-bearing rock formations This list ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
