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Raphiophoridae
Raphiophoridae is a family of small to average-sized trilobites that first occurred at the start of the Ordovician and became extinct at the end of the Middle Silurian. Anatomy All raphiophorids are blind, with headshields (or Trilobite#Cephalon, cephalons) that are triangular to subcircular, and many carry long, trailing genal spines, a forward-directed rapier-like spine on the central raised area (or Trilobite#Cephalon, glabella), or both, with the glabella often inflated and the natural fracture lines (or Trilobite#Dorsal sutures, sutures) of the cephalon coinciding with its margin. Trilobite#Thorax, The thorax typically has five to seven segments (except for the genera ''Taklamakania'', ''Pseudampyxina'', ''Nanshanaspis'', and ''Kongqiangheia'', which have only 3). As mentioned before, all raphiophorids are blind. Many, if not most, genera have no eyes whatsoever, though a few, such as ''Lehnertia'', have vestigial tubercles that correspond to the compound eyes of their ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ampyx (trilobite)
''Ampyx'' is an Ordovician-Silurian genus of Asaphida, Asaphid trilobites of the family (biology), family Raphiophoridae. Species of ''Ampyx'' are characterized by three extended spines on the head-shield, one spine derived from each free cheek, and one spine emanating from the Trilobite#Cephalon, glabellum. Species include ''Ampyx linleyensis'' (Lanvirn Series, Lanvirn-Caradoc Series, Caradoc series). Species of ''Ampyx'' grew to an average length of . Collective behaviour Fossils of the trilobite ''Ampyx priscus'', dating back about 480 million years ago, have been recently described as clustered in lines along the ocean floor. The animals were all mature adults, and were all facing the same direction as though they had formed a conga line or a peloton. It has been suggested they line up in this manner to migrate, much as spiny lobsters migrate in single-file queues. Or perhaps they are getting together for mating. The findings suggest animal collective behaviour has very ea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raphiophorus
''Raphiophorus'' is a genus of the family Raphiophoridae in the Ordovician and Silurian The Silurian ( ) is a geologic period and system spanning 23.5 million years from the end of the Ordovician Period, at million years ago ( Mya), to the beginning of the Devonian Period, Mya. The Silurian is the third and shortest period of t ... periods. It has been reported from East Asia, North Africa, North and South America, and especially Europe. References Raphiophoridae Fossil taxa described in 1854 Asaphida genera {{Asaphida-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lonchodomas
''Lonchodomas'' is a genus of trilobites, that lived during the Ordovician. It was eyeless, like all raphiophorids, and had a long straight sword-like frontal spine, that gradually transforms into the relatively long glabella. Both the glabellar spine and the backward directed genal spines are subquadrate in section. ''Lonchodomas'' has five thorax segments and the pleural area of the pygidium has two narrow furrows. ''Lonchodomas'' occurred in what are today Argentina, Canada (Newfoundland), Estonia, Latvia, Norway, Sweden, the Russian Federation (Leningrad OblastA.V. Krylov (2003).New data on trilobites from Hecker mud mounds (Ordovician) in the Leningrad region (in Russian). ''Vestnik Sankt-Petersburgskogo Universiteta, Seriya Geologiya i Geografiya'' 3(33):95-96) and the United States (Oklahoma, Virginia). Distribution * ''L. carinatus'' is found in the Upper Ordovician of the United States (Lower Member and Botetourt limestone Member, of the Edinburgh Formation, Shenan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Globampyx
''Globampyx'' is an extinct genus raphiophorid trilobites. It lived during the later part of the Arenig stage of the Ordovician Period, approximately 478 to 471 million years ago. Species of the genus are known from Canada (southeastern British Columbia), Norway (Svalbard) and Sweden. Distribution * ''G. sinalae'' is known from the Middle Ordovician of Canada (''Orthidiella'' brachiopod zone, Glenogle Shales Formation, North White River Section, British Columbia, 471.8-468.1 Ma) * ''G. trinucleoides'' is known from the Middle Ordovician of Svalbard (''Psephosthenaspis microspinosa'' small shelly zone, Olenidsletta Member, Valhallfonna Formation, Ny friesland, 471.8-457.5 Ma) Description The headshield (or cephalon) of ''Globampyx'' is densely covered with very small granules. The central raised area of the cephalon (or glabella The glabella, in humans, is the area of skin between the eyebrows and above the nose. The term also refers to the underlying bone that is sligh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Damghanampyx
''Damghanampyx'' is an extinct genus of trilobites in the family Raphiophoridae. It has been reported from the Ordovician period of Iran. The name ''Damghanampix'' is taken from the city of Damghan in Semnan province of Iran. Description ''Damghanampix'' had a simple cephalon and a large and prominent glabella, which distinguished itself from all trilobites Trilobites (; meaning "three-lobed entities") are extinct marine arthropods that form the class Trilobita. One of the earliest groups of arthropods to appear in the fossil record, trilobites were among the most successful of all early animals, .... References Raphiophoridae Ordovician Asia Fossil taxa described in 2007 {{Asaphida-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bulbaspis
''Bulbaspis'' ("bulb shield") is a late Ordovician genus of asaphid trilobites of the family Raphiophoridae found primarily in upper Ordovician-aged deepwater marine strata of Kazakhstan, China, and possibly Tasmania. Species of ''Bulbaspis'' are similar to other raphiophorids such as ''Ampyx'' and ''Raphiophorus'', save that the long spine that emanates from the glabella of the latter two genera has been modified into a knob-like or bulb-like structure in ''Bulbaspis'' that developed incrementally in the animal's growth.Zhiqiang, Zhou, and Zhou Zhiyi. "Late Ordovician trilobites from the Zhusilenghaierhan area, Ejin Banner, western Inner Mongolia, China."MEMOIR-ASSOCIATION OF AUSTRALASIAN PALAEONTOLOGISTS 32 (2006): 383. The function of the bulb is currently unknown: one hypothesis suggests sexual selection may have had a role in its evolution in the genus.Knell, Robert J., and Richard A. Fortey. "Trilobite spines and beetle horns: sexual selection in the Palaeozoic?." Biology ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kongqiangheia
''Kongqiaoheia rotundata'' is an asaphid trilobites of the family Raphiophoridae that lived during the late Caradoc of Inner Mongolia, China. ''K. rotundata'' was originally grouped with the so-called Taklamakaniinae, a paraphyletic group of tiny, dwarfed raphiophorids that lived in a deepwater environment in what is now the Tarim Basin The Tarim Basin is an endorheic basin in Xinjiang, Northwestern China occupying an area of about and one of the largest basins in Northwest China.Chen, Yaning, et al. "Regional climate change and its effects on river runoff in the Tarim Basin, Ch ..., including '' Pseudampyxina'', '' Nanshanaspis'', and '' Taklamakania''. Like these other genera, ''K. rotundata'' has only three thoracic segments, probably due to paedomorphic dwarfism: other raphiophorid trilobites have at minimum five thoracic segments. Morphology As with other "taklamakaniids," ''K. rotundata'' had a disk-shaped body with a semi-circular cephalon, a bulbous glabellum, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cnemidopyge
''Cnemidopyge'' is a genus of trilobites that lived during the Ordovician. Like all Raphiophorids it is blind, with a cephalon that is subtriangular to subsemicircular, carrying genal spines and a forward directed rapier-like spine on the central raised area (or glabella), with the front of the glabella inflated and the natural fracture lines (or sutures) of the cephalon coinciding with its margin. It may be easily distinguished from other raphiophorids by the rectangular thorax with 6 segments, where other genera have a different number of segments and segments change in width over the length of the thorax. Uniquely in this genus, the inner pleural region of the frontal segment is enlarged.Whittington, H. B. et al. (1997) Treatise on Invertebrate Paleontology. Part O, Revised, Volume 1 – Trilobita – Introduction, Order Agnostida, Order Redlichiida. Also the axis (or rhachis) and pleural fields of the pygidium The pygidium (: pygidia) is the posterior body part or shield of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mendolaspis
''Mendolaspis'' is an extinct genus of trilobites. It lived during the Arenig stage of the Ordovician Period The Ordovician ( ) is a geologic period and system, the second of six periods of the Paleozoic Era, and the second of twelve periods of the Phanerozoic Eon. The Ordovician spans 41.6 million years from the end of the Cambrian Period Ma (mill ..., approximately 478 to 471 million years ago. References Raphiophoridae Asaphida genera Ordovician trilobites Fossils of Norway Fossils of Argentina {{Asaphida-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trilobite
Trilobites (; meaning "three-lobed entities") are extinction, extinct marine arthropods that form the class (biology), class Trilobita. One of the earliest groups of arthropods to appear in the fossil record, trilobites were among the most successful of all early animals, existing in oceans for almost 270million years, with over 22,000 species having been described. Because trilobites had wide diversity and an easily fossilized mineralised exoskeleton made of calcite, they left an extensive fossil record. The study of their fossils has facilitated important contributions to biostratigraphy, paleontology, evolution, evolutionary biology, and plate tectonics. Trilobites are placed within the clade Artiopoda, which includes many organisms that are morphologically similar to trilobites, but are largely unmineralised. The relationship of Artiopoda to other arthropods is uncertain. Trilobites evolved into many ecological niches; some moved over the seabed as predators, scavengers, or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ludlow
Ludlow ( ) is a market town and civil parish in Shropshire (district), Shropshire, England. It is located south of Shrewsbury and north of Hereford, on the A49 road (Great Britain), A49 road which bypasses the town. The town is near the confluence of the rivers River Corve, Corve and River Teme, Teme. The oldest part is the medieval Defensive wall, walled town, founded in the late 11th century after the Norman Conquest, Norman conquest of England. It is centred on a small hill which lies on the eastern bank of a bend of the River Teme. Situated on this hill are Ludlow Castle and the parish church, St Laurence's Church, Ludlow, St Laurence's, the largest in the county. From there the streets slope downward to the rivers River Corve, Corve and River Teme, Teme, to the north and south respectively. The town is in a sheltered spot beneath Mortimer Forest and the Clee Hills, which are clearly visible from the town. Ludlow has nearly 500 listed buildings, including examples of med ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
