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Eldredgeops
''Eldredgeops'' is a genus of trilobites in the order Phacopida, family Phacopidae, known from the late Middle and earliest Upper Devonian of Morocco and the USA. Description Like in all sighted Phacopina, the eyes of ''Eldredgeops'' are composed of very large (0.5mm in '' Eldredgeops rana''), separately set lenses without a common cornea (so called schizochroal eyes), and like almost all other Phacopina, the articulate mid-length part of the body (or thorax) in ''Eldredgeops'' has 11 segments. In contrast to the related ''Phacops'', ''Eldredgeops'' generally has a raised ridge along the ventral margin of the cephalon, the glabella is more inflated, the lateral parts of the preoccipital ring are rectangular (and not round), the palpebral area and palpebral lobe are larger than in ''P. latifrons'' (the type species of ''Phacops''), and there is no fold right behind the posterior vertical row of lenses nor an isolated raised area just below the lenses. Distribution All pha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eldredgeops Rana
''Eldredgeops rana'' (formerly ''Phacops rana'') is a species of trilobite from the middle Devonian period. Their fossils are found chiefly in the northeastern United States, and southwestern Ontario. Because of its abundance and popularity with collectors, ''Eldredgeops rana'' was designated the Pennsylvania state fossil by the state's General Assembly on December 5, 1988. Description ''Eldredgeops rana'' can be recognized by its large eyes (which remind some observers of a frog's eyes—the specific name ''rana'' is a reference to a common frog), its fairly large size (up to 6 inches long), and its habit of rolling up into a ball like a pill bug ("volvation"). In order to protect themselves from predators, ''Eldredgeops rana'' would roll into a ball with its hard exoskeleton on the outside as protection. Many other trilobites possessed the same ability, but ''Eldredgeops rana'' nearly perfected it. The slightest amount of sediment would trigger their senses, and ''El ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eldredgeops Norwoodensis
''Eldredgeops'' is a genus of trilobites in the order Phacopida, family Phacopidae, known from the late Middle and earliest Upper Devonian of Morocco and the USA. Description Like in all sighted Phacopina, the eyes of ''Eldredgeops'' are composed of very large (0.5mm in ''Eldredgeops rana''), separately set lenses without a common cornea (so called schizochroal eyes), and like almost all other Phacopina, the articulate mid-length part of the body (or thorax) in ''Eldredgeops'' has 11 segments. In contrast to the related ''Phacops'', ''Eldredgeops'' generally has a raised ridge along the ventral margin of the cephalon, the glabella is more inflated, the lateral parts of the preoccipital ring are rectangular (and not round), the palpebral area and palpebral lobe are larger than in ''P. latifrons'' (the type species of ''Phacops''), and there is no fold right behind the posterior vertical row of lenses nor an isolated raised area just below the lenses. Distribution All phac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phacops
''Phacops'' is a genus of trilobites in the order Phacopida, family Phacopidae, that lived in Europe, northwestern Africa, North and South America and China from the Late Ordovician until the very end of the Devonian, with a broader time range described from the Late Ordovician.''Phacops'' at .org It was a rounded animal, with a globose head and large eyes, and probably fed on . ''Phacops'' is often found rolled up (" volvation"), a biological defense ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Milwaukee Formation
The Milwaukee Formation is a fossil-bearing geological formation of Middle Devonian age in Milwaukee County, Wisconsin. It stands out for the exceptional diversity of its fossil biota. Included are many kinds of marine protists, invertebrates, and fishes, as well as early trees and giant fungi. Once a prolific source of fossils, the Milwaukee Formation exposures are now mostly buried, inaccessible, on private property, or located in areas where collecting is prohibited. Most of these exposures are or were located along the Milwaukee River and Lake Michigan shore. History and significance Early interest in the Milwaukee Formation was mainly of a commercial or other practical nature. Strata apparently of what would later be known as the Milwaukee Formation were utilized as early as the 1670s, when French visitors used “pitch” (natural asphalt) from the rock exposures on the shore of Lake Michigan near Milwaukee to patch their boats. The rock was later used to produce lime or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trilobite
Trilobites (; meaning "three lobes") are extinct marine arthropods that form the class Trilobita. Trilobites form one of the earliest-known groups of arthropods. The first appearance of trilobites in the fossil record defines the base of the Atdabanian stage of the Early Cambrian period () and they flourished throughout the lower Paleozoic before slipping into a long decline, when, during the Devonian, all trilobite orders except the Proetida died out. The last extant trilobites finally disappeared in the mass extinction at the end of the Permian about 252 million years ago. Trilobites were among the most successful of all early animals, existing in oceans for almost 270 million years, with over 22,000 species having been described. By the time trilobites first appeared in the fossil record, they were already highly diversified and geographically dispersed. Because trilobites had wide diversity and an easily fossilized exoskeleton, they left an extensive fossil record. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phacopida
Phacopida ("lens-face") is an order of trilobites that lived from the Late Cambrian to the Late Devonian. It is made up of a morphologically diverse assemblage of taxa in three related suborders. Characteristics Phacopida had 8 to 19 thoracic segments and are distinguishable by the expanded glabella, short or absent preglabellar area, and schizochroal (Phacopina) or holochroal (Cheirurina and Calymenina) eyes. Schizochroal eyes are compound eyes with up to around 700 separate lenses. Each lens has an individual cornea which extended into a rather large sclera. The development of schizochroal eyes in phacopid trilobites is an example of post-displacement paedomorphosis. The eyes of immature holochroal Cambrian trilobites were basically miniature schizochroal eyes. In Phacopida, these were retained, via delayed growth of these immature structures (post-displacement), into the adult form. ''Eldredgeops rana'' ( Phacopidae) and '' Dalmanites limulurus'' (Dalmanitidae) are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phacopidae
Phacopidae is a family of phacopid trilobites that ranges from the Lower Ordovician to the Upper Devonian, with representatives in all paleocontinents. Description As in all Phacopina, the eyes (if present) consist of very large (0.5 mm in ''Phacops rana''), separately set lenses without a common cornea (so called schizochroal eyes). However, several phacopids have very few lenses, such as the species of the genera ''Cryphops'', ''Denckmannites'', ''Dienstina'', ''Eucryphops'', ''Nephranops'', and ''Plagiolaria'', or lack eyes altogether, like ''Afrops'', ''Dianops'', ''Ductina'', and ''Trimerocephalus''. The natural fracture lines (sutures) of the head run along the top edges of the compound eye. From the back of the eye these cut to the side of the head ( proparian) and not to the back. In front of the eye, the right and left facial sutures connect in front of the inflated glabella and consequently the free cheeks (or librigenae) are yoked as a single piece. In some of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trilobite
Trilobites (; meaning "three lobes") are extinct marine arthropods that form the class Trilobita. Trilobites form one of the earliest-known groups of arthropods. The first appearance of trilobites in the fossil record defines the base of the Atdabanian stage of the Early Cambrian period () and they flourished throughout the lower Paleozoic before slipping into a long decline, when, during the Devonian, all trilobite orders except the Proetida died out. The last extant trilobites finally disappeared in the mass extinction at the end of the Permian about 252 million years ago. Trilobites were among the most successful of all early animals, existing in oceans for almost 270 million years, with over 22,000 species having been described. By the time trilobites first appeared in the fossil record, they were already highly diversified and geographically dispersed. Because trilobites had wide diversity and an easily fossilized exoskeleton, they left an extensive fossil record. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tully Formation
Tully may refer to: People * Tully (surname), origins and history of the Tully surname in Ireland ** List of people with surname Tully * List of people with given name Tully * Marcus Tullius Cicero, or Cicero, a Roman philosopher, politician, lawyer and orator Places Australia * Tully (Parish), New South Wales, a civil parish of Yungnulgra County * Tully, Queensland, a town in the Cassowary Coast Region * Tully Falls, Queensland * Tully River, Queensland, Australia France * Tully, Somme, a commune in France Ireland *Tully, a civil parish in Dublin, Republic of Ireland * Tully, County Galway, a village on the Renvyle Peninsula * Tully, County Kildare, a civil parish in County Kildare, Republic of Ireland * Tully, County Offaly, a townland spanning Ardnurcher and Kilmanaghan civil parishes, barony of Kilcoursey, County Offaly, Republic of Ireland United Kingdom * Tully, County Fermanagh, a townland in County Fermanagh, Northern Ireland * Tully, County Londonderr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Traverse Group
The Traverse Group is a geologic group in Michigan, comprising middle Devonian limestones with calcareous shale components. Its marine fossils notably include Michigan's state stone, the Petoskey stone (the extinct coral ''Hexagonaria percarinata''), among other corals and records of ancient marine life. A range of trilobites has also been found in the Traverse Group. The Traverse Group outcrops in Emmet and Charlevoix counties along the northwestern shore of Michigan's lower peninsula. Its formations are Gravel Point, Charlevoix Limestone, Petoskey, and Whiskey Creek. The Gravel Point Formation consists of a lithographic gray to brown limestone with shale beds up to 0.5 meters thick; it also includes chert nodules and bioherms (fossilized reef mounds). The Charlevoix Limestone is a mildly argillaceous limestone with interbedded coquina. The Petoskey Formation is an arenaceous limestone named for its locale (Petoskey, Michigan), and contains the eponymous Petoskey stones. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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