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Lichida
Lichida is an order of typically spiny trilobite that lived from the Furongian to the Devonian period. These trilobites usually have 8–13 thoracic The thorax or chest is a part of the anatomy of humans, mammals, and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main divisions of the crea ... segments. Their exoskeletons often have a grainy texture or have wart or spine-like tubercles. Some species are extraordinarily spiny, having spiny thoracic segments that are as long or longer than the entire body, from cephalon (head) to pygidium (tail). The sections of the pygidia are leaf-like in shape and also typically end in spines. The order is divided into two families, Lichidae, and Lichakephalidae. Some experts group the families of the closely related order Odontopleurida within Lichida, too, whereupon the family is then divided into three superfamilies, Dameselloidea, con ... [...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. The stu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ceratarges
''Ceratarges'' was a genus of lichid Trilobite from the Middle Devonian. It lived in what is now western Europe and Morocco Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to .... References Lichida Middle Devonian first appearances Late Devonian animals Late Devonian genus extinctions Devonian trilobites of Africa Fossil taxa described in 1901 Paleozoic life of the Northwest Territories {{lichida-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctinurus
''Arctinurus boltoni'' is a large (up to 30 cm) lichid trilobite of the mid-Silurian. This trilobite reached about eight inches in length, though the normal adult carapace was about four inches. It lived in moderately deep-water in semi-tropical regions. ''Arctinurus'' fossils have been found in Europe and North America. ''Arctinurus'' was first reported during the construction of the Erie Canal through soft Silurian shales and mudstones in upstate New York. Before the late 1990s, complete ''Arctinurus'' fossils were very rare. The vast majority of complete specimens were commercially mined near Middleport New York, USA, in a shallow quarry in the Rochester Formation, and the trilobite is now relatively common in museum, university and private collections. ''Arctinurus'' tended to have epibiont An epibiont (from the Ancient Greek meaning "living on top of") is an organism that lives on the surface of another living organism, called the basibiont ("living underneath"). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Odontopleurida
Odontopleurida is an order (biology), order of very spinose trilobites closely related to the trilobites of the order Lichida. Some experts group the Odontopleurid families, Odontopleuridae and Damesellidae, within Lichida. Odontopleurids tend to have convex, bar-shaped cephalons, and lobed, knob-shaped glabella that extend to, or almost to the anterior margin. Many, if not almost all odontopleurids have long spines that are derived either from the margins of the exoskeleton, or from granular or tubercular ornamentation, or both. Many odontopleurids are so spinose so as to be described as having "spines on (their) spines." Odontopleurids have 8 to 13 thoracic segments, with Odontopleuridae odontopleurids having no more than 10, and Damesellidae odontopleurids having no more than 13. The pygidium tends to be very small, and invariably has long spines emanating from it in all known genera. Genera of Damesellidae are restricted to Middle to Upper Cambrian marine strata, and may ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acanthopyge
''Acanthopyge'' is an extinct genus of lichid trilobite that lived during the Devonian The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, whe .... Very few ''A. consanguinea'' from the Devonian of Oklahoma have been found, and only a handful of complete specimens from Morocco, and many so-called ''Acanthopyge''-specimens from Morocco are fake. References Sources ''Photos of A. consanguinea'' External links '' Trilobite info (Sam Gon III)'' Lichida [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pygidium
The pygidium (plural pygidia) is the posterior body part or shield of crustaceans and some other arthropods, such as insects and the extinct trilobites. In groups other than insects, it contains the anus and, in females, the ovipositor. It is composed of fused body segments, sometimes with a tail, and separated from thoracic segments by an articulation.Shultz, J.W. (1990). Evolutionary Morphology And Phylogeny of Arachnida. Cladistics 6: 1–38. Chelicerates In arachnids, the pygidium is formed by reduction of the last three opisthosomal segments to rings where there is no distinction between tergites and sternites. A pygidium is present in Palpigradi, Amblypygi, Thelyphonida, Schizomida, Ricinulei and in the extinct order Trigonotarbida. It is also present in early fossil representatives of horseshoe crabs. Trilobites In trilobites, the pygidium can range from extremely small (much smaller than the head, or cephalon) to larger than the cephalon. They can be smooth, as in order ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terataspis Grandis
''Terataspis'' is a comparatively huge, 60 centimetre long lichid trilobite genus from the Early Devonian, about 397 million years ago. It lived in a shallow sea in what is now New York State and Ontario. No whole specimens have been found, only disarticulated fragments of its exoskeleton, but enough fragments have been found to allow researchers to form reconstructions of the whole animal. The genus only contains one species, ''T. grandis''. ''Terataspis grandis'', like many other trilobites, was presumed to have been a detritivore that was also an opportunistic predator, preying on small burrowing animals, such as molluscs, worms, or arthropods. Description Almost the entire body of ''T.grandis'' is covered with spines and tubercles of varying sizes. The pygidium is large and shield-like with four pairs of slightly curved barbed spines on the sides. The thorax consists of around 11 segments. The cephalon is characterized by its swollen front portion and longitudinal furro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apatolichas
''Apatolichas'' is an extinct genus from a well-known class of fossil marine arthropods, the trilobites. It lived during the later part of the Arenig stage of the Ordovician Period The Ordovician ( ) is a geologic period and system, the second of six periods of the Paleozoic Era. The Ordovician spans 41.6 million years from the end of the Cambrian Period million years ago (Mya) to the start of the Silurian Period Mya. The ..., approximately 478 to 471 million years ago. References Ordovician trilobites of North America Extinct animals of North America Paleozoic life of Newfoundland and Labrador {{trilobite-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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