Trilobita

From Palaeos.org

o Arthropoda
`--o TRILOBITA
   |?-Agnostina
   `--+--o Redlichiida
      |  |--Olenellina
      |  `--Redlichiina
      |--Corynexochida
      |--Phacopida
      |--Lichida
      `--o Librostoma
         |--Proetida
         |--Harpetida [Harpoidea]
         |--Ptychopariida
         |?-Eodiscina
         `--Asaphida

The trilobites are an extinct class of marine arthropods. By the time true trilobites appear in the fossil record, during the Cambrian, they are already highly diverse and possess two characteristics that likely served them well to survive in the Paleozoic seas, a well- mineralized exoskeleton, and a highly advanced visual system. They particularly flourished during the Cambrian when the peak number of families existed and went extinct in the Permian-Triassic extinction after a prolonged decline beginning in the Late Devonian extinction.

[edit] Taxonomy

<==Trilobita
   |  i. s.: Cyrtosymbole
   |         Encrinurus
   |         Liocalymene
   |         Xystridura Whitehouse 1936
   |         Tonkinella
   |         Kootenia
   |         Megagraulos
   |           |--M. breviscapus Kobayashi 1962
   |           `--M. medius Kobayashi 1962
   |         Metagraulos
   |         Fenghuangella Yang 1978
   |         Torifera Wolfart 1974
   |         Goniagnostus
   |           |--G. confluens [=Agnostus nathorsti confluens]
   |           `--G. nathorsti [=Agnostus nathorsti]
   |         Triplagnostus lomondensis
   |         Xenostegium
   |         Ogygites
   |         Ogygopsis klotzi
   |         Asaphiscidae
   |           |--Asaphiscus wheeleri
   |           `--Blountia
   |         Cedarellus felix Lazarenko 1966
   |         Amorphella Rosova 1963
   |           `--A. modesta Rosova 1963
   |         Changshanocephalus
   |         Lioparia
   |         Irvingella
   |           |--I. taitzuhoensis
   |           `--I. tropica
   |         Erixanium
   |         Kaolishania
   |           |--K. australis Shergold 1972
   |           `--K. pustulosa
   |         Tingocephalus
   |         Pseudosolenopleura kotoi
   |         Pseudoliostracina monkei
   |         Maduiya Rosova 1963 [incl. Maspakites Lazarenko 1968]
   |         Kaninia Walcott & Resser 1924
   |         Pedinocephalus Ivshin 1956
   |           `--‘Maladioidella’ convexolimbata Endo in Endo & Resser 1937
   |         Taenoria expansa Palmer 1960
   |         Kainellidae
   |           |--Kainella meridionalis
   |           `--Richardsonella
   |                |--R. arctostriata (Raymond 1937)
   |                |--R. elongata Rasetti 1944
   |                |--R. eurekensis Kobayashi 1935
   |                `--R. megalops (Billings 1860)
   |         Parabolina
   |           |--P. acanthura (Angelin 1854)
   |           `--P. brevispina Westergaard 1922
   |         Simulolenus Palmer 1965
   |           `--S. quadrisulcatus Palmer 1965
   |         Parabolinites Henningsmoen 1957
   |           `--‘Parabolinella’ laticauda Westergaard 1922
   |         Protopeltura intermedia Westergaard 1922
   |         Bienvillia corax
   |         Crucicephalus ocellatus Shergold 1972
   |         Amzasskiella mirabilis Petrunina 1960
   |         Koptura
   |           |--K. biloba Kobayashi 1935
   |           `--K. quadrata
   |         Temnura granulosa Kobayashi 1935 [=Temnoura granosa (l. c.)]
   |         Golasaphus momedahensis
   |         Acanthopyge (Mephiarges)
   |           |--A. (M.) bifida
   |           |--A. (M.) consanguinea
   |           `--A. (M.) mephisto
   |         Gravicalymene
   |         Kiskinella cristata Romanenko & Romanenko 1962
   |         Agraulos affinis Billings 1872
   |         Bailiaspis inflata Lake 1940
   |         Condylopyge carinata Westergård 1936
   |         Staurocephalus clavifrons Angelin 1854
   |         Homalonotus Koenig 1825
   |         Eoredlichia intermedia
   |         Proetida
   |           |--Kaskia chesterensis
   |           `--Anisopyge cooperi
   |         Alacephalus Repina 1960
   |           `--A. latus Romenenko 1978
   |         Erbiopsis Lermontova 1940
   |           `--E. coangustus Romanenko 1969
   |--Naraoia [incl. Liwia, Tegopelte; Eotrilobitacea, Nectaspida]
   |    |--N. compacta
   |    `--‘Tegopelte’ gigas Whittington 1985
   `--Trilobitacea
        |  i. s.: Olenoides serratus
        |--Agnostida
        `--Polymera

* Type species of genus indicated

[edit] References

Alcock, F. J. 1938. Geology of Saint John region, New Brunswick. Geological Survey of Canada Memoir 216: 1-65.

Bousfield, E. L. 1995. A contribution to the natural classification of Lower and Middle Cambrian arthropods: Food-gathering and feeding mechanisms. Amphipacifica 2: 3-34.

Conway Morris, S. 1998. The Crucible of Creation. Oxford University Press: Oxford.

Crawford, R. L. 1992. Catalogue of the genera and type species of the harvestman superfamily Phalangioidea (Arachnida). Burke Museum Contributions in Anthropology and Natural History 8: 1-60.

Eckert, J. D., & C. E. Brett. 2001. Early Silurian (Llandovery) crinoids from the Lower Clinton Group, western New York State. Bulletins of American Paleontology 360: 1-88.

Fletcher, T. P. 2005. Holaspid variation in the solenopleurid trilobite Parasolenopleura gregaria (Billings, 1865) from the Cambrian of Newfoundland. Palaeontology 48 (5): 1075-1089.

Gould, S. J. 1989. Wonderful Life. Vintage: London.

Guppy, D. J., & A. A. Öpik. 1950. Discovery of Ordovician rocks, Kimberley Division, W. A. The Australian Journal of Science 12: 205-206.

Hong, P. S., J. G. Lee & D. K. Choi. 2003. Trilobites from the Lejopyge armata zone (upper Middle Cambrian) of the Machari Formation, Yongwol Group, Korea. Journal of Paleontology 77 (5): 895-907.

Kruse, P. D. 2002. Biostratigraphic potential of Middle Cambrian hyoliths from the eastern Georgina Basin. Alcheringa 26: 353-398.

Lane, N. G., C. G. Maples & J. A. Waters. 2001. Revision of Late Devonian (Famennian) and some Early Carboniferous (Tournaisian) crinoids and blastoids from the type Devonian area of north Devon. Palaeontology 44 (6): 1043-1080.

Přibyl, A., J. Vaněk & I. Pek. 1985. Phylogeny and taxonomy of family Cheiruridae (Trilobita). Acta Universitatis Palackianae Olomucensis Facultas Rerum Naturalium Geographica-Geologica XXIV 83: 107-193.

Prothero, D. R. 1998. Bringing Fossils to Life: An introduction to paleobiology. WCB McGraw-Hill: Boston.

Rong, J.-Y., R.-B. Zhan & J. Jin. 2004. The Late Odovician and Early Silurian pentameride brachiopod Holorhynchus Kiaer, 1902 from north China. Journal of Paleontology 78 (2): 287-299.

Sánchez, T. M., & N. E. Vaccari. 2003. Ucumariidae new family (Bivalvia, Anomalodesmata) and other bivalves from the Early Ordovician (Tremadocian) of northwestern Argentina. Ameghiniana 40 (3): 415-424.

Shergold, J. H. 1980. Late Cambrian trilobites from the Chatsworth Limestone, western Queensland. Bureau of Mineral Resources, Geology and Geophysics – Bulletin 186: 1-111.

Shu, D.-G., L. Chen, J. Han & X.-L. Zhang. 2001. An Early Cambrian tunicate from China. Nature 411: 472-473.

Sutton, M. D., D. E. G. Briggs, D. J. Siveter, D. J. Siveter & P. J. Orr. 2002. The arthropod Offacolus kingi (Chelicerata) from the Silurian of Herefordshire, England: Computer based morphological reconstructions and phylogenetic affinities. Proceedings of the Royal Society of London Series B – Biological Sciences 269: 1195-1203.

Thomson, K. S., & K. S. W. Campbell. 1971. The structure and relationships of the primitive Devonian lungfish – Dipnorhynchus sussmilchi (Etheridge). Yale University Peabody Museum of Natural History Bulletin 38: 1-109.

Whittington, H. B., & D. E. G. Briggs. 1985. The largest Cambrian animal, Anomalocaris, Burgess Shale, British Columbia. Philosophical Transactions of the Royal Society of London 309: 569-609.

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