Micragnostus

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Micragnostus
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Trilobita
Order: Agnostida
Genus:Micragnostus
Howell, 1935c

Micragnostus is a genus of trilobite in the order Agnostida, which existed in what is now north Wales. It was described by Howell in 1935, and the type species is Micragnostus calvus, which was originally described as a species of Agnostus by Lake in 1906. [1]

Trilobite class of arthropods (fossil)

Trilobites are a group of extinct marine arachnomorph 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 era before beginning a drawn-out decline to extinction when, during the Devonian, all trilobite orders except the Proetids died out. Trilobites disappeared in the mass extinction at the end of the Permian about 252 million years ago. The trilobites were among the most successful of all early animals, existing in oceans for over 300 million years.

Agnostida order of arthropods (fossil)

Agnostida is an order of arthropod which first developed near the end of the Early Cambrian period and thrived during the Middle Cambrian. They are present in the Lower Cambrian fossil record along with trilobites from the Redlichiida, Corynexochida, and Ptychopariida orders. The last agnostids went extinct in the Late Ordovician.

Wales Country in northwest Europe, part of the United Kingdom

Wales is a country that is part of the United Kingdom and the island of Great Britain. It is bordered by England to the east, the Irish Sea to the north and west, and the Bristol Channel to the south. It had a population in 2011 of 3,063,456 and has a total area of 20,779 km2 (8,023 sq mi). Wales has over 1,680 miles (2,700 km) of coastline and is largely mountainous, with its higher peaks in the north and central areas, including Snowdon, its highest summit. The country lies within the north temperate zone and has a changeable, maritime climate.

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<i>Phacops</i> genus of arthropods (fossil)

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<i>Isotelus</i> genus of trilobites

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Burmeisteria is a genus of trilobites in the order Phacopida that existed during the lower Devonian in what is now South Africa. It was described by Salter in 1865, and the type species is Burmeisteria herschelii, which was originally described under the genus Homalonotus by Murchison in 1839. It also contains the species B. accraensis, B. acuminata, and B. noticus. The type locality was the Bokkeveld Group.

Calymenella is a genus of trilobites in the order Phacopida, which existed in what is now France during the upper Ordovician. It was described by Bergeron in 1890, and the type species is Calymenella boisseli. The species was described from the Glauzy Formation in the Montagne Noire mountain range.

<i>Chasmops</i> genus of trilobites (fossil)

Chasmops is a trilobite in the order Phacopida that existed during the upper Ordovician in what is now Estonia. It was described by McCoy in 1849, and the type species is Chasmops odini, which was originally described under the genus Calymene by Eichwald in 1840. It also contains the species C. maxima.

Coronura is a trilobite in the order Phacopida, that existed during the Middle Devonian in what is now New York, U.S.A. It was described by Hall and Clarke in 1888, and the type species is Coronura aspectans, which was originally described under the genus Asaphus by Conrad in 1841. The species was described from the Onondaga Formation. Fossils of Coronura have also been found in Indiana, and in the Emsian to Givetian Floresta Formation, Altiplano Cundiboyacense, Colombia.

Denckmannites is a trilobite in the order Phacopida, that existed during the upper Silurian in what is now the Czech Republic. It was described by Wedekind in 1914, and the type species is Denckmannites volborthi, which was originally described under the genus Phacops by Barrande in 1852. It also contains the species Denckmannites morator, and Denckmannites primaevus. The type locality was the Kopanina Formation.

Encrinuroides is a genus of trilobites in the order Phacopida, that existed during the upper Ordovician in what is now Wales. It was described by Reed in 1931, and the type species is Encrinuroides sexcostata, which was originally described under the genus Cybele by Salter in 1848. It also contains the species, Encrinuroides enshiensis, Encrinuroides insularis, and Encrinuroides rarus. The type locality was in the Sholeshook Limestone Formation.

Hintzeia is a genus of trilobites in the order Phacopida, that existed during the lower Ordovician in what is now the United States. It was described by Harrington in 1957, and the type species is Hintzeia aemula, which was originally described under the genus Protopliomerops by Hintze in 1953. Harrington also moved two other Protopliomerops species, P. celsaora and P. firmimarginis, under Hintzeia. The generic name is derived from that of the type species' author. The type locality was the Fillmore Formation in Utah.

<i>Kanoshia</i> genus of trilobites (fossil)

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Oncagnostus is a genus of trilobite in the order Agnostida, which existed in what is now Shandong, China. It was described by Whitehouse in 1936, and the type species is Oncagnostus hoi, which was originally described as a species of Agnostus by Sun in 1924.

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References

  1. Available Generic Names for Trilobites P.A. Jell and J.M. Adrain.