Trilobites 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 trilobites disappeared in the mass extinction at the end of the Permian about 251.9 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.
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.
Cromus is a genus of phacopid trilobites in the family Encrinuridae, that existed during the upper Silurian in what is now the Czech Republic. The genus was described by Barrande in 1852, and the type species is C. intercostatus. It also contains the species C. canorus.
Cybele is a genus of trilobites in the order Phacopida, that existed during the middle Ordovician in what is now Sweden. It was described by Loven in 1846, and the type species is Cybele bellatula, which was originally described dubiously under the genus Calymene by Dalman in 1827. The type locality was in Östergötland.
Daytonia is a trilobite in the order Phacopida, that existed during the lower Silurian in what is now the United States. It was described by D. J. Holloway in 1981, and the type species is Daytonia werthneri, which was originally described under the genus Dalmanites by August Foerste in 1885. It also contains the species, Daytonia mekon. The type locality for the genus was the Brassfield Formation, in Ohio.
Deacybele is a genus of trilobites in the order Phacopida, that existed during the upper Ordovician in what is now Ireland. It was described by Whittington in 1965, and the type species is Deacybele arenosa, which was originally described under the genus Calymene by McCoy in 1846. The type locality was the Avoca Formation.
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.
Dianops is a genus of phacopid trilobite in the order Phacopida, that existed during the upper Devonian in what is now Germany. It was described by Richter and Richter in 1923, and the type species is Dianops limbatus, which was originally described under the genus Phacops by Richter in 1848. The type locality was in Saalfeld, Thuringia.
Digonus is a genus of trilobites in the order Phacopida, that existed during the lower Devonian in what is now Germany. It was described by Gurich in 1909, and the type species is Digonus gigas, which was originally described under the genus Homalonotus by Roemer in 1843. It also contains the species Digonus accraensis and Digonus noticus, Digonus vialai, and Digonus zemmourensis. The type locality was in the Harz mountains.
Dipleura is a genus of trilobites in the order Phacopida. It was described by Green in 1832, and the type species is Dipleura dekayi. The type locality was in the Hamilton Group in New York.
Encrinurella is a genus of trilobite in the order Phacopida, that existed during the middle Ordovician in what is now Burma. It was described by Reed in 1915, and the type species is Encrinurella insangensis, which was originally described under the genus Pliomera by Reed in 1906. The type locality was the Naungkangyi Beds.
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.
Eulomina a genus of trilobites in the order Phacopida, that existed during the lower Ordovician in what is now the Czech Republic. It was described by Ruzicka in 1931, and the type species is Eulomina mitratum, which the author originally described under the genus Euloma in 1926. The type locality was the Trenice Formation.
Forteyops 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 Pribyl and Vanek in 1985, and the type species is Forteyops sexapugia, which was originally described under the genus Kawina by Ross in 1951. The type locality was the Garden City Formation in Utah.
Frencrinuroides is a genus of trilobites in the order Phacopida, that existed during the upper Ordovician in what is now the United States. It was described by Lesperance and Desbiens in 1995, and the type species is Frencrinuroides capitonis, which was originally described under the genus Encrinuroides by Frederickson in 1964. The type locality was the Bromide Formation in Oklahoma.
Hammanopyge is a genus of trilobites in the order Phacopida, that existed during the upper Ordovician in what is now Scotland. It was described by Pribyl and Vanek in 1985, and the type species is Hammanopyge unica, which was originally described under the genus Acidaspis by Thomson in 1857. The type locality was the Balclatchie 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.
Kanoshia is a genus of trilobites in the order Phacopida, that existed during the middle Ordovician in what is now Utah, USA. It was described by Harrington in 1957, and the type species is Kanoshia kanoshensis, which was originally described under the genus Pseudomera by Hintze in 1953. It also contains the species K. depressus and K. reticulata. The generic name is derived from the type species' epithet, which in turn is derived from the name of the type locality, the Kanosh Formation.
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.
Bumastus is an extinct genus of corynexochid trilobites which existed from the Early Ordovician period to the Late Silurian period. They were relatively large trilobites, reaching a length of 6 in (15 cm). They were distinctive for their highly globular, smooth-surfaced exoskeleton. They possessed well-developed, large compound eyes and were believed to have dwelled in shallow-water sediments in life.
