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Weymouthiidae
The Weymouthiidae Kobayashi 1943 are an extinct family of eodiscinid agnostid trilobites. They lived during the late Lower Cambrian and earliest Middle Cambrian (Botomian to Delamaran) in the so-called ''Olenellus''- and ''Eokochaspis''-zones in the former paleocontinents of Laurentia, Avalonia, Gondwana. The Weymouthiidae are all blind and lack free cheeks. Taxonomy Ancestors The Weymouthiidae have developed from a stock within the Hebediscidae The Hebediscidae Kobayashi, 1944, are a family of trilobites belonging to the order Agnostida that lived during the Lower Cambrian (Atdabanian to Toyonian). They are small or very small, and have a thorax of two or three segments. The Hebediscida .... Descendants The Weymouthiidae are a paraphyletic family because the Agnostina suborder is nested within it, particularly in the clade that further consists of the genera ''Mallagnostus'', ''Chelediscus'', ''Tannudiscus'' and ''Jinghediscus''. The trend in the Weymouthiid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acidiscus
''Acidiscus'' Rasetti, 1966, is a genus of Eodiscinid trilobite belonging to the family Weymouthiidae Kobayashi T. (1943), Order Agnostida Salter (1864). It lived during the Botomian stage = late Lower Cambrian Stage 4 (upper of two stages subdividing the unnamed Series 2); the upper Botomian boundary corresponds to base of the Middle Cambrian, Miaolingian Series and Wuliuan stage. Etymology * ''A. birdi'' is named for Dr. John M. Bird who collected the holotype. * ''A. hexacanthus'' is derived from the Greek hexa "six" and acanthos "spine", for having two pairs of border spines in addition to one pair of genal spines. * ''A. theristes'' is named after a Greek in the Iliad (an epic poem written by Homer around 800 B.C.E.) who accused Agamemnon of greed and Achilles of cowardice during the Trojan War. Taxonomy A cladogram showing the relationship between several species of the genera ''Acidiscus'', '' Bolboparia'' and '' Stigmadiscus'' ''Acidiscus'' is most closely related to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mallagnostus
''Mallagnostus'' Howell, 1935, is a trilobite genus belonging to the family Weymouthiidae Kobayashi T. (1943), Order Agnostida Salter (1864) according to Whittington ''et al''. 1997. It lived during the late Lower Cambrian, with remains found in USA (New York), Canada (Newfoundland), Spain, England, Russia (Tuva, Gorno-Altayskaya), Mongolia, and the early Middle Cambrian as reported from China (Tian Shan) and Russia (Yakutia). Taxonomy ''Mallagnostus'' was originally described as belonging to the Agnostina, but it is more appropriately placed in the Eodiscina. Within the Weymouthiidae, ''Mallagnostus'' belongs to a clade that further includes ''Tannudiscus ''Tannudiscus'' Pokrovskaya (1959) is a genus of Eodiscinid trilobites belonging to the family Weymouthiidae Kobayashi T. (1943), Order Agnostida (Salter 1864). It lived during the late Lower Cambrian, with remains found in Canada (Newfoundland), ...'', '' Jinghediscus'' and the Agnostina. Distribution * ''M. desidera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chelediscus
''Chelediscus'' Rushton, 1966, is a genus of Eodiscinid trilobite belonging to the family Weymouthiidae The Weymouthiidae Kobayashi 1943 are an extinct family of eodiscinid agnostid trilobites. They lived during the late Lower Cambrian and earliest Middle Cambrian (Botomian to Delamaran) in the so-called ''Olenellus''- and ''Eokochaspis''-zon ... Kobayashi T. (1943), Order Agnostida Salter (1864). The Treatise assigns this genus to the Calodiscidae; Cotton and Fortey (2005) however move it to the Weymouthiidae. ''Chelediscus'' lived during the later part of the Botomian stage.. Chelediscus is known from upper lower Cambrian strata in England, Newfoundland, New York State and Russia (Rushton, 1966; Fletcher, 2003; Rasetti, 1967; Jell ''in'' Kaesler, 1997; Distribution * The Holotype of ''C. acifer'' Rushton (1966, p. 19, pl. 2, figs. 26 a - e), is A 57104, held at the Sedgwick Museum of Earth Sciences, University of Cambridge and was collected by Rushton from about ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Analox
''Analox'' Rasetti, 1966 is a genus of Eodiscinid trilobites belonging to the family Weymouthiidae Kobayashi T. (1943), Order Agnostida (Salter 1864) SALTER, J. W. 1864: On some new fossils from the Lingula-flags of Wales. ''Quarterly Journal of the Geological Society of London'', 20, 233–241. It lived during the Botomian stage. It can easily be distinguished from other trilobites by the two furrows that extend forwards and sidewards from the front of the glabella. Distribution ''Analox bipunctata'' is known from the Lower Cambrian of the United States. ).Whittington, H. B. et al. Part O, Treatise on Invertebrate Paleontology. Revised, Volume 1 – Trilobita – Introduction, Order Agnostida, Order Redlichiida. 1997 Type locality for ''Analox bipunctata'' is Rasetti's (1966) locality cs-4 in an unnamed limestone Formation which is exposed in several outcrops on a hill (Griswold Farm) about 1 mile southeast of North Chatham, Columbia County, New York State, USA; the faunu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marocconus
''Marocconus'' is an extinct genus from a well-known class of fossil marine arthropods, the trilobites. It is still debated if it lived at the very end of the Lower Cambrian or at the very beginning of the Middle Cambrian. ''Marocconus notabilis'' is the only known species in this genus (i.e. the genus is monotypic). Taxonomy ''Marocconus'' replaces ''Cephalopyge'' Geyer, 1988, which is a junior homonym of '' Cephalopyge'' Hanel, 1905, a nudibranch. ''Cephalopyge'' however, is still widely used for this trilobite, and the new name ''Marocconus'' has only been mentioned one time in the scientific literature. Distribution ''Marocconus notabilis'' is known from the latest Lower Cambrian or earliest Middle Cambrian of MoroccoJbel Wawrmast Formation Anti-Atlas Mountains).Whittington, H. B. et al. Part O, Treatise on Invertebrate Paleontology. Revised, Volume 1 – Trilobita – Introduction, Order Agnostida, Order Redlichiida. 1997 Ecology ''Marocconus notabilis'' occurs in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jinghediscus
''Jinghediscus'' Xiang & Zhang, 1985 is a genus of Eodiscinid trilobite belonging to the family Weymouthiidae Kobayashi T. (1943), Order Agnostida (Salter 1864) SALTER, J. W. 1864: On some new fossils from the Lingula-flags of Wales. ''Quarterly Journal of the Geological Society of London'', 20, 233–241. It lived during the lower Middle Cambrian, with remains found in China (Xinjiang) and Australia (Queensland). Species ''Jinghediscus nummularius'' Xiang and Zhang, 1985. Distribution Description Like all Weymouthiidae, ''Jinghediscus'' lacks eyes and facial sutures. Cephalon semi-elliptical. Glabella has one transglabellar furrow and inflated posterior lobe that widens towards rear. Preglabellar field broad (sag.) and confluent with uniformly wide (tr.) genal areas. Occipital ring (L0) ill-defined and without spine. cephalic border is only gently convex and of uniform width. Pygidium with strongly conical axis composed of ten axial rings; pleural fields smooth and def ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acimetopus
''Acimetopus'' Rasetti, 1966, is a genus of Eodiscinid trilobite belonging to the family Weymouthiidae Kobayashi (1943), Order Agnostida Salter (1864). SALTER, J. W. 1864: On some new fossils from the Lingula-flags of Wales. Quarterly Journal of the Geological Society of London, 20, 233–241. It lived during the Botomian stage. = late Lower Cambrian Stage 4 (upper of two stages subdividing the un-named Series 2); the upper Botomian boundary corresponds to base of the Middle Cambrian, Miaolingian Series and Wuliuan stage. Type species ''Acimetopus bilobatus'' Rasetti, 1966, from his locality cs-4 in limestone beds which form several outcrops on a hillside at Griswold Farm, about 1 mile southeast of North Chatham, Columbia County, New York State, USA; the associated faunule is referred to as the ''Acimetopus bilobatus'' faunule due to the nominate species being one of the most common and characteristic trilobites. Distribution ''Acimetopus'' is known from the Lower Cambri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ninadiscus
''Ninadiscus'' Korobov, 1980, is a genus of Eodiscinid trilobite belonging to the family Weymouthiidae Kobayashi (1943), Order Agnostida Salter (1864). SALTER, J. W. 1864: On some new fossils from the ''Lingula''-flags of Wales. ''Quarterly Journal of the Geological Society of London'', 20, 233–241. It lived during the Botomian Stage = late Lower Cambrian Stage 4 (upper of two stages subdividing the un-named Series 2); the upper Botomian boundary corresponds to the base of the Middle Cambrian, the Miaolingian Series and Wuliuan The Wuliuan stage is the fifth stage of the Cambrian, and the first stage of the Miaolingian Series of the Cambrian. It was formally defined by the ICS in 2018. Its base is defined by the first appearance of the trilobite species ''Oryctocephalu ... Stage. Distribution ''Ninadiscus'' is known from the Lower Cambrian (Botomian) of northwestern Mongolia (Egyngolskaya Suite) and the USA (New York). WHITTINGTON, H. B. ''et al''., Part O, Treatise on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oodiscus
''Oodiscus'' is an extinct genus of small size (about ) trilobite, with three known species. It lived during the Toyonian in what are now Canada and the USA. Distribution ''O. subgranulatus'' is known from the upper Lower Cambrian of the USA (New York, Griswold Farm) and Canada (Newfoundland). Ecology ''Oodiscus'' occurs in association with other Weymouthiidae (''Acidiscus'', ''Acimetopus'', ''Analox'', '' Bathydiscus'', '' Bolboparia'', ''Leptochilodiscus'', ''Serrodiscus''), and ''Calodiscus''.Whittington, H. B. et al. Part O, Treatise on Invertebrate Paleontology. Revised, Volume 1 – Trilobita – Introduction, Order Agnostida, Order Redlichiida. 1997 Description Like all Agnostida, ''Oodiscus'' is diminutive and the headshield (or cephalon) and tailshield (or 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 anu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serrodiscus
''Serrodiscus'' Richter and Richter 1941. is a genus of Eodiscinid trilobite belonging to the family Weymouthiidae Kobayashi T. (1943), Order Agnostida (Salter 1864). It lived during the late Lower Cambrian, with remains found in Canada (Newfoundland & Nova Scotia), China (Gansu), The United Kingdom (England), Germany (Silesia), Poland (Holy Cross Mountains), the Russian Federation (Tuva, Gorno-Altayskaya, Kuznetsk Alatau), and the United States (Massachusetts, New York State). It is named for the spines on the ventral side of the 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 compo ..., which give it a serrated impression. Fletcher & Theokritoff (2008) designated Shaw’s (1950, pl. 79, fig. 24) specimen of “''Weymouthia nobilis'' (Ford, 1872)” as the holotype of a new s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meniscuchus
''Meniscuchus'' is an extinct genus from a well-known class of fossil marine arthropods, the trilobites. It lived during the Botomian stage, which lasted from approximately 522 to 516 million years ago. This faunal stage was part of the Cambrian Period. ''Meniscuchus'' has been found in the USA (Alaska, New York), Canada (Newfoundland, Quebec), Russia (Siberian Platform, Gorno-Altayskaya) and Australia (New South Wales).Whittington, H. B. et al. Part O, Treatise on Invertebrate Paleontology. Revised, Volume 1 – Trilobita – Introduction, Order Agnostida, Order Redlichiida. 1997 Distribution * ''M. helena'' has been found in the Lower Cambrian of Canada (Newfoundland). * ''M. menetus'' is known from the Lower Cambrian of Australia (Cymbric Vale Formation, New South Wales). * ''M. nanus'' was collected in Alaska. Description Like all Eodiscina, the headshield (or cephalon) and tailshield (or pygidium) are approximately equal in size. Like all Weymouthiidae, ''Meniscuchus'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Runcinodiscus
''Runcinodiscus'' Rushton (''in'' Bassett ''et al.'' 1976, p. 636-7) is a genus of Lower Cambrian Eodiscinid trilobite belonging to the family Weymouthiidae The Weymouthiidae Kobayashi 1943 are an extinct family of eodiscinid agnostid trilobites. They lived during the late Lower Cambrian and earliest Middle Cambrian (Botomian to Delamaran) in the so-called ''Olenellus''- and ''Eokochaspis''-zon ... (Kobayashi 1943), Order Agnostida (Salter 1864). Type Species By Monotypy and original designation, ''Runcinodiscus index'' Rushton (''in'' Bassett ''et al.'' 1976). Holotype is A 15360 in the collection of the Sedgwick Museum of Earth Sciences, University of Cambridge. Locality and age The Type specimen (Cobbold, 1931) was collected from the ''Protolenus'' Limestone (Ac5) omley Series 180m south of Comley Quarry, near Church Stretton, Shropshire, England - according to Morris (1988, p.205). Remarks Fletcher & Theokritoff (2008) designated Shaw’s (1950, pl. 7 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
