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Cyclopygidae
Cyclopygidae is a family of asaphid trilobites from the Ordovician. Cyclopygids had aextratropical distribution, and there is evidence that they lived in darker parts of the water column (around 175m deep). Cyclopygids are characterized by enlarged eyes, with a wide angle of view, both horizontal and vertical, reminiscent of the eyes of dragonflies. These typically touch the glabella directly on the side. Cyclopygids all lack genal spines, but '' Symphysops'' carries a forward directed frontal spine on the glabella. It is presumed that at least the members of the genus '' Pricyclopyge'' swam upside down and had bioluminescent organs on the third thorax segment. Cyclopygids had between 7 and 5 thorax segments, a wide and stout axis, and short side lobes (or pleurae). Taxonomy The genera of Cyclopygidae are grouped into the following subfamilies: *Cyclopyginae ** '' Cyclopyge'' Hawle & Corda, 1847 ** '' Delgamella'' Marek, 1961 ** '' Gastropolus'' Whittard, 1966 ** '' He ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emmrichops
''Emmrichops'' is a genus of average size trilobite (about ), assigned to the Cyclopygidae family, that lived during the Middle Ordovician (Llanvirn), and have been found in what are today the Czech Republic and in Wales. Like other cyclopygids, it has huge eyes, that occupy almost the entire free cheeks (or librigenae), six thorax segments and a wide tail shield. Like the other cyclopygids, ''Emmrichops'' probably lived hunting plankton in the water column. Only one species, ''E. planicephala'', has been described sofar. Etymology ''Emmrichops'' was named in honor of the German geologist Hermann Emmrich (1815–1879). Distribution * ''Emmrichops planicephala'' is known from the Ordovician of Wales (''Hustedograptus teretiusculus'' biozone, Llanfawr Mudstones Formation, Builth inlier, Llandeilian Stage of the Llanvirn Series) and the Czech Republic (Dobrotiva Formation, near Svatá Dobrotivá, Vokovice and Veleslavín, all Prague Basin). References Cyclopygidae ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prospectatrix
''Prospectatrix'' is a genus of trilobites of average size, that lived in the Lower Ordovician and is probably ancestral to the other genera of the Cyclopygidae Cyclopygidae is a family of asaphid trilobites from the Ordovician. Cyclopygids had aextratropical distribution, and there is evidence that they lived in darker parts of the water column (around 175m deep). Cyclopygids are characterized by en ... family. Its eyes are only moderately enlarged and it has six or seven thorax segments. Etymology ''Prospectatrix'' is derived from the Latin, meaning “early observer”, expressing that this genus was an early representative of the extremely well-sighted cyclopygids. The species epithet is derived from the Latin ''exquisita'', meaning excellent, refers to the well preserved type specimens. Distribution * ''P. genatenta'' occurs in the Lower Ordovician of the United Kingdom (Upper Tremadocian, ''Shumardia (Conophrys) salopiensis'' Zone, Shineton Shale, Shineton, Shr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclopyge (trilobite)
''Cyclopyge'' is a genus of small to average size trilobites that lived during the Ordovician. Like all members of the family Cyclopigidae, it has very large convex eyes, that cover most of the free cheeks, and in some species touch each other. The eyes almost touch the large glabella. The occipital ring has merged with the rest of the glabella. The glabella does not extend into a frontal thorn. The cephalon lacks genal spines. The 6 thorax segments have short pleurae. The pygidium is rather large, and often rather effaced. These are features that also occur in other Cyclopygidae, and are indications of a pelagic lifestyle.Whittington, H. B. et al. Part O, Treatise on Invertebrate Paleontology. Revised, Volume 1 – Trilobita – Introduction, Order Agnostida, Order Redlichiida. 1997 Taxonomy The genus was first named ''Egle'' by Barrande, but that name was not available, since it was used by Robineau-Desvoidy before for willow catkin flyof the Anthomyiidae The Anthomyiid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circulocrania
''Circulocrania'' is an extinct genus of trilobites in the family Cyclopygidae. The genus 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. Th ..., approximately 478 to 471 million years ago. References Cyclopygidae Asaphida genera Early Ordovician trilobites of Europe Fossils of Great Britain {{Asaphida-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pricyclopyge
''Pricyclopyge'' is a genus of trilobites assigned to the family Cyclopygidae that occurs throughout the Ordovician. ''Pricyclopyge'' had aextratropical distribution, and there is evidence that it lived in darker parts of the water column (around 175m deep). ''Pricyclopyge'' has huge eyes, an inverted pear-shaped glabella, six thorax segments, with on the 3rd two small discs.Whittington, H. B. et al. (1997) Treatise on Invertebrate Paleontology. Part O, Revised, Volume 1 – Trilobita – Introduction, Order Agnostida, Order Redlichiida. ''Pricyclopyge'' is known from what are today China, the Czech Republic, France, and the United Kingdom.Paleobiology Database Description Like other cyclopygids, ''Pricyclopyge'' lacks genal spines. ''Pricyclopyge'' has six thorax segments of which the third from the front carries two very characteristic round discs that are presumed to have been bioluminescent organs, and if true, this suggests that ''Pricyclopyge'' swam upside down. It ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symphysops
''Symphysops'' is a genus of trilobites of average size, belonging to the Cyclopygidae family. It had a cosmopolitan distribution and lived from the Middle to the Upper Ordovician (Llanvirn to Ashgill). It has been found in Canada (Quebec and Newfoundland), China, the Czech Republic (Bohemia), Iran, Ireland, Kazakhstan, Poland, Morocco, Spain, Scotland and Wales.Whittington, H. B. et al. Part O, Treatise on Invertebrate Paleontology. Revised, Volume 1 – Trilobita – Introduction, Order Agnostida, Order Redlichiida. 1997 The name ''Symphysops'' refers to the fused eyes, common to the species of this genus. Some (sub)species of the cyclopygid genera ''Cyclopyge'' and ''Pricyclopyge'' share this character, but ''Symphysops'' uniquely combines the merged eye with a frontal thorn on the head and the "lower eyelid". Etymology ''Symphysops'' is the combination of the Ancient Greek σύν (syn) "together", φύσις (physis) "growth" and ὄψις (opsis) "sight", referring to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sagavia
''Sagavia'' is a genus of trilobites that lived during the Middle and Upper Ordovician in what are now Northwest and Southeast China, North Kazakhstan and Wales. It is a typical cyclopygid that can be distinguished by its large but separate eyes, elongated glabella, five thorax segments and a pygidium with clearly defined axis and border. Species and distribution * ''S. chuanxiensis'' (Li & Xiao, 1984) (synonym A synonym is a word, morpheme, or phrase that means exactly or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are al ... ''Microparia (Microparia) chuanxiensis'') is found in the Middle and Upper Ordovician of China (late Caradoc-Ashgill, top of the Pagoda Formation, limestone block in a Triassic melange accumulation at Shiqu; Yuanba, Hougou and Liangshan, Nanzheng; Dangmengou and Zhuyegou, Ningqiang; Qishuba and Gaoqiaogou, Mianxian; all ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asaphida
Asaphida is a large, morphologically diverse order of trilobites found in marine strata dated from the Middle Cambrian until their extinction during the Silurian. Asaphida contains six superfamilies (Anomocaroidea, Asaphoidea, Cyclopygoidea, Dikelocephaloidea, Remopleuridoidea and Trinucleioidea), but no suborders. Asaphids comprise some 20% of described fossil trilobites. In 2020, the superfamily Trinucleoidea was proposed to be raised to an order ( Trinucleida) and removed from Asaphida. Morphology The Asaphids generally have cephalon (head) and pygidium (tail) parts similar in size, and most species have a prominent median ventral suture. Heads are often flat, and carapace furrows in the head area are often faint or not visible. Thoracic segments typically number 5 - 12, though some species have as few as two and some as many as 30. They also generally have a wide doublure, or rim, that surrounds the cephalon. This causes some specimens to be described as having a char ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aspidaeglina
''Aspidaeglina'' is an extinct genus from a well-known class of fossil marine arthropods, the trilobites. It lived during the early part of the Arenig stage of the Ordovician Period, a faunal stage which lasted from approximately 473 to 470 million years ago. Distribution * ''A. miranda'' is known from the Lower Ordovician of the Czech Republic (Arenig In geology, the Arenig (or Arenigian) is a time interval during the Ordovician period and also the suite of rocks which were deposited during this interval. History The term was first used by Adam Sedgwick in 1847 with reference to the "Arenig ..., Klabava Formation). * ''A. striata'' occurs in the Lower Ordovician of China (Pagoda Formation of southwestern Shaanxi). References Cyclopygidae Asaphida genera Fossils of the Czech Republic Fossils of China Ordovician trilobites of Asia Early Ordovician trilobites of Europe {{Asaphida-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
