off sea level 180m rising to 220m in Caradoc and falling sharply to 140m in end Ordovician glaciations ... SR issue 5898 ref The Ordovician IPAc en icon r d v n is a geologic period geologic period ... Period. The Ordovician, named after the Celts Celtic tribe of the Ordovices , was defined ... that they should be placed in a period of their own. While recognition of the distinct Ordovician ... during the Ordovician as it did in the Cambrian , although the end of the period was marked by a Ordovician ... on land. Dating The Ordovician Period started at a major extinction event called the Cambrian Ordovician extinction events some time about 488.3 1.7 annum Mya million years ago , and lasted for about 44.6 million years. It ended with the Ordovician Silurian extinction event , about 443.7 ... The boundary chosen for the beginning both of the Ordovician Period and the Tremadocian stage ... to place many more species in time relative to the beginning of the Ordovician Period. Subdivisions ... to subdivisions of the Ordovician Period. In 2008, the ICS erected a formal international system ... 10.1111 j.1502 3931.2009.00169.x ref The Ordovician Period in Britain was traditionally broken into Early .... The corresponding rocks of the Ordovician System are referred to as coming from the Lower, Middle ... Gamach Late Ordovician Ashgill Rawtheyan Richmond Late Ordovician Ashgill Cautleyan Richmond Late Ordovician Ashgill Pusgillian Maysville Richmond Late Ordovician Ashgill Trenton Middle Ordovician Caradoc Onnian Maysville Eden Middle Ordovician Caradoc Actonian Eden Middle Ordovician Caradoc Marshbrookian Sherman Middle Ordovician Caradoc Longvillian Sherman Middle Ordovician Caradoc Soundleyan Kirkfield Middle Ordovician Caradoc Harnagian Rockland Middle Ordovician Caradoc Costonian Black River Middle Ordovician Caradoc Chazy Middle Ordovician Llandeilo Llandeilo Middle Ordovician Llandeilo Whiterock Middle Ordovician Llanvirn Llanvirn Middle Ordovician Llanvirn Cassinian Early ... more details
Refimprove date June 2011 Infobox rockunit name Putilovo village type quarry age Middle Ordovician region Europe country Russia In a quarry near what is now Putilovo village , Russia near Saint Petersburg , are large deposits of Ordovician clay . In this clay the most abundant genus is Asaphus , a trilobite . fact date June 2011 List of species Trilobites Image Asaphus expansus robustus.JPG thumb 150px Asaphus expansus Image WLA hmns Trilobite Hoplolichoides conicotuberculata.jpg thumb 150px Hoplolichoides Image Pseudoasaphus praecurrens MHNT.PAL.2003.439.jpg thumb 150px Pseudoasaphus gallery File Trilobite Ordovicien 8127.jpg Cheirurus gallery class wikitable Genus Species Asaphus A. kowalevski , A. expansus , A. latus Prochasmops P. praecurrens Dysplanus D. acutigenia Hoplolichoides H. conicotuberculatus Cybele C. panderi Illaenus I. tauricornis Cheirurus C. sp. Pseudoasaphus P. praecurrens Ptychopyge P. lesnikova References Yvonne Howells, Ordovician Trilobites of St. Petersburg Region External links http www.indiana9fossils.com Trilobites Russian Trilobites.htm Categories Category Ordovician trilobites ... more details
Annotated image Extinction The Cambrian Ordovician extinction event occurred approximately 488 million years ago Mya unit m.y.a. . This early Phanerozoic Eon geology Eon extinction event eliminated many brachiopods and conodonts , and severely reduced the number of trilobite species. It was preceded by the less documented but probably worse End Botomian mass extinction End Botomian extinction event around 517 m.y.a. and the Dresbachian event about 502 m.y.a. The Cambro Ordovician event ended the Cambrian Geologic period Period , and led into the Ordovician Period in the Paleozoic Geologic era Era . Image Extinction Intensity.svg 200px Theories Glaciation Anoxic sea water Depletion of oxygen in marine waters See also End Botomian extinction event, circa 517 Mya unit m.y.a. Dresbachian extinction event, circa 502 m.y.a. Geologic time scale Furongian , Late or Upper Cambrian period Early Ordovician period Further reading Gradstein, Felix, James Ogg, and Alan Smith, eds., 2004. A Geologic Time Scale 2004 Cambridge University Press . Hallam, A. and Paul B. Wignall, 1997. Mass extinctions and their aftermath Oxford University Press . Webby, Barry D. and Mary L. Droser, eds., 2004. The Great Ordovician Biodiversification Event Columbia University Press . External links http www.scotese.com eordclim.htm Early Ordovician Climate http park.org Canada Museum extinction camcause.html Speculated Causes For the Cambrian Extinction ExtEvent nav Category Extinction events Category Climate history Category Cambrian Category Ordovician es Extinciones masivas del C mbrico Ordov cico fr Extinction du Cambrien hu Kambrium ordov cium kihal si esem ny nn Den kambrisk ordovikiske masseutryddinga pt Extin o do Cambriano Ordoviciano sv Kambrium ordovicium utd endet zh ... more details
The Great Ordovician Biodiversification Event GOBE or Ordovician radiation was a evolutionary radiation diversification of animal life throughout ref name Munnecke2010 the Ordovician period, just 40 million years after the Cambrian explosion , ref name Servais2008 whereby the distinctive Cambrian fauna fizzled out to be replaced with a Palaeozoic fauna rich in Filter feeder suspension feeder and pelagic animals. ref name Servais2010 It followed a series of Cambrian Ordovician extinction events extinction events at the Cambrian Ordovician boundary, and the resulting fauna went on to dominate the Palaeozoic relatively unchanged. ref name Droser2003 Marine diversity increased to levels typical of the Palaeozoic, ref name Marshall2006 cite doi 10.1146 annurev.earth.33.031504.103001 ref and morphological disparity was similar to today s. ref name Bush2007 cite doi 10.1666 06013.1 ref ref name Bambach2007 cite doi 10.1111 j.1475 4983.2006.00611.x ref The diversity increase was neither global nor instantaneous it happened at different times in different places. Ref name Droser2003 Consequently, there is unlikely to be a simple or straightforward explanation for the event the interplay of many geological and ecological factors likely produced the diversification. ref name Munnecke2010 Cite doi 10.1016 j.palaeo.2010.08.001 ref Causes Possible causes include changes in palaeogeography or tectonic ..., Muir last2 Muir year 2008 first2 Lucy A. title Unravelling Causal Components of the Ordovician ... bryozoan Cincinnatian Upper Ordovician of southeastern Indiana. If the Cambrian Explosion ... displays the Ordovician radiation beautifully both diversity and disparity peaked in the middle Ordovician. ref name Servais2008 cite doi 10.1111 j.1502 3931.2008.00115.x ref The warm waters ... new food chains at the end of the Cambrian into the early Ordovician. ref cite pmc 2749442 ref See also Cambrian explosion References reflist Category Ordovician geochronology stub paleo stub ... more details
annotated image Extinction The Ordovician Silurian extinction event , or quite commonly the Ordovician extinction , was the second largest of the five major extinction event s in Earth s history in terms .... Note The program attributes the Ordovician extinction sic explicitly as the second most grievously ... title THE LATE ORDOVICIAN MASS EXTINCTION Annual Review of Earth and Planetary Sciences, 29 1 331 ... Canada Museum extinction ordcause.html title Causes of the Ordovician Extinction ref Evidence for the glaciation ... level and glacially driven cooling are likely driving agents for the Ordovician mass extinction ... It marks the boundary between the Ordovician and following Silurian period. During this extinction ... faunal stage towards the end of the Ordovician, ref name Munnecke2010 which had more ... on it. The strata have been detected in late Ordovician Stratum rock strata of North Africa and then adjacent ... repeatedly to drop and rise the vast shallow intra continental Ordovician seas withdrew, which eliminated ..., A.L. et al title Did a gamma ray burst initiate the late Ordovician mass extinction? journal ..., B.C. title Late Ordovician geographic patterns of extinction compared with simulations of astrophysical .... S.A. et al title A major drop in seawater 87Sr 86Sr during the Middle Ordovician Darriwilian Links ... the Late Ordovician outgassing from major volcanism was balanced by heavy weathering of the uplifting ... Geoscience Programme IGCP , following a successful probe of the Ordovician biodiversification, has ..., sea level, volcanism, plate movements and extraterrestrial influences, of the Ordovician biodiversification, this end Ordovician extinction, and the ensuing Silurian radiation. ref cite web url http ... Oxford University Press . Webby, Barry D. and Mary L. Droser, eds., 2004. The Great Ordovician Biodiversification ... Maastricht verniers.doc Jacques Veniers, The end Ordovician extinction event abstract of Hallam and Wignall, 1997. ExtEvent nav Category Extinction events Category Climate history Category Ordovician ... more details
Automatic taxobox display parents 3 fossil range Ordovician authority MacGabhann & Murray, 2010 Seputus is a discoid fossil from the Ordovician that may represent a Cambroernid . ref name Murray2010 cite doi 10.3318 IJES.2010.28.1 ref References reflist Category Ordovician life ... more details
Taxobox name Reteocrinus fossil range Middle Ordovician Late Ordovician image image width image caption regnum Animal ia phylum Echinodermata subphylum Crinozoa classis Crinoid ea ordo Diplobathrida genus Reteocrinus genus authority subdivision ranks Species subdivision Reteocrinus is an extinct genus of sea lily that lived in the Middle Ordovician Middle to Late Ordovician . Its remains have been found in North America . Sources http www.fieldmuseum.org evolvingplanet popUps CO43.html Reteocrinus in the Field Museum s Evolving Planet External links http paleodb.org cgi bin bridge.pl?action checkTaxonInfo&taxon no 31657 Reteocrinus in the Paleobiology Database portal Paleontology Category Crinoidea Category Prehistoric invertebrates Category Ordovician animals Category Prehistoric animals of North America paleo echinoderm stub ... more details
Italic title Taxobox name Illaenus fossil range fossil range Middle Ordovician image Illaenus tauricornis Trilobites.jpg image caption Illaenus tauricornis regnum Animal ia phylum Arthropod a classis Trilobite Trilobita ordo Corynexochida familia Illaenidae genus Illaenus genus authority Johan Wilhelm Dalman Dalman , 1827 Illaenus is a genus of trilobite s from Russia and Morocco , from the middle Ordovician . See also Ordovician fauna of Putilovo village References Yvonne Howells, Ordovician Trilobites of St. Petersburg Region External links http www.indiana9fossils.com Trilobites Russian Trilobites.htm http www.paleoart.com catalog 382 Illaenus Category Ordovician trilobites trilobite stub ... more details
Italic title Taxobox name Constellaria fossil range fossil range Ordovician regnum Animal ia phylum Bryozoa classis Stenolaemata ordo Cystoporida familia Constellariidae genus Constellaria genus authority James Dwight Dana Dana , 1846 type species Constellaria constellata type species authority Dana, 1849 Constellaria is an extinct genus of bryozoan from the Ordovician . References Dinosaurs to Dodos An Encyclopedia of Extinct Animals by Don Lessem and Jan Sovak portal Paleontology Category Ordovician animals Paleo stub ... more details
italic title Taxobox name Mcqueenoceras fossil range Ordovician image regnum Animal ia phylum Mollusca classis Cephalopod a subclassis Nautiloid ea ordo Endocerida familia Proterocameroceratidae genus Mcqueenoceras Mcqueenoceras is an early Endocerida endocerid , a nautilus from the OrdovicianOrdovician period similar in overall form to Clitendoceras , from which it may have been derived. It lived during the later stages of the Early Ordovician lower Ordovician . McQueenoceras , like Clitendoceras , has ventral siphuncle but the endocones are thicker on the ventral side and thinner on the dorsal. Also the sutures in McQueenoceras retreat rearward, forming lobes as they cross the venter. References Flower, R. H. 1964 Memoir 12, The Nautiloid Order Ellesmeroceratida Cephalopoda , pp 126, 147, 148. NMBM&MR, Socorro N.M. Teichert, C, 1964, Mcqueenoceras , p 166 in Proterocameroceratidae, pp 166 170 in the Treatise on Invertebrate Paleontology , Vol K. GSA and Univ Kansas Press. Category Nautiloids Category Ordovician animals Category Prehistoric cephalopods ... more details
The Andean Saharan glaciation was from 460 annum Ma to 430 Ma, during the late Ordovician and the Silurian period. Paleozoic Footer Category Ordovician Category Silurian Category Glaciology Category Ice ages A discussion of the several known ice ages is presented at http academic.emporia.edu aberjame ice labs lab03.htm Ice Ages Glaciology stub ... more details
The Zitai Formation is a geological sequence of Middle Ordovician origin, that occurs along the southeastern edge of the Yangtze Platform in southern China . It is a purple red limestone with a few interspersed yellow green shale beds. It contains a fossil fauna dominated by trilobite s and nautiloid s. Category Ordovician geologic formations geologic formation stub China stub ... more details
Italic title Taxobox regnum Animal ia phylum Arthropod a classis Trilobite Trilobita ordo Asaphida familia Raphiophoridae genus Lonchodomas genus authority Lonchodomas is an extinct genus of trilobite from the Ordovician period. References Dinosaurs to Dodos An Encyclopedia of Extinct Animals by Don Lessem and Jan Sovak portal Paleontology Category Ordovician trilobites Trilobite stub ... more details
Tremadoc may refer to Tremadog , a village in northern Wales of which Tremadoc is an alternate, anglicised name . The Tremadocian , the first internationally recognized stage of the Ordovician Period of the Paleozoic Era. disambig ... more details
Taxobox image Haeckel Blastoidea.jpg image caption blastoidea blastoids regnum Animal ia phylum Echinodermata subphylum Blastozoa subdivision ranks Classes subdivision Class Eocrinoidea Cambrian Silurian Class Parablastoidea Ordovician Class Rhombifera Cystoidea , part Ordovician Devonian Class Diploporita Cystoidea, part Ordovician Devonian Class Blastoidea Ordovician Permian Blastozoa is a subphylum of extinct animals belonging to Phylum Echinoderm ata. This subphylum is characterized by the presence of hydrospire s. ref http paleo.cortland.edu tutorial Echinoderms echinoderms2.htm Echinoderms Crinozoa & Blasozoa ref References reflist External links http www.mcz.harvard.edu Departments InvertPaleo Trenton Intro PaleoPage TrentonFauna Echinodermata Blastozoa Blastozoa.htm Harvard Subphylum Blastozoa paleo echinoderm stub Category Echinoderms es Blastozoa ... more details
italictitle Taxobox name Neoasaphus fossil range Ordovician image Neoasaphus.jpg image width 250px image caption regnum Animal ia phylum Arthropod a classis Trilobita ordo Asaphida familia Asaphidae genus Neoasaphus genus authority subdivision ranks Species subdivision Neoasaphus is a genus of trilobite from the Ordovician Period of Europe . Sources The Great Ordovician Biodiversification Event The Critical Moments and Perspectives in Earth History and Paleobiology by Barry D. Webby, Florentin Paris, Mary L. Droser, and Ian G. Percival portal Paleontology Category Asaphida Category Ordovician trilobites Category Prehistoric animals of Europe trilobite stub ... more details
Orphan date February 2009 Unreferenced date February 2009 Dendrograptus is an extinct genus of Graptolite from the Lower Ordovician . Category Graptolites paleo stub portal Paleontology ... more details
Automatic taxobox fossil range fossil range Ordovician genus Hemithecella Hemithecella is a problematic genus of Ordovician mollusc proposed by Stinchcomb and Darrough in 1995. ref cite jstor 1306279 ref Hemithecella belongs to what are informally known as multiplated molluscs it is found in the late Cambrian of the Ozarks and the Lower Ordovician of the same region as well as in Minnesota and the southern Appalachian Mountains . Hemithecella has muscle scars identical to a monoplacophora n and not the musculature of a chiton to which some authors have suggested the multiplated molluscs belong. It is therefore classified in the Mattheviidae . ref Upper Cambrian Chitons ref References Reflist Category Ordovician animals Category Prehistoric molluscs paleo mollusc stub ... more details
Taxobox name Apedolepis fossil range fossil range Ordovician regnum Animal ia phylum Chordata subphylum Vertebrata genus Apedolepis genus authority Young, 1997 ref cite journal last Young first Gavin C. year 1997 title Ordovician microvertebrate remains from the Amadeus Basin, central Australia journal Journal of Vertebrate Paleontology volume 17 pages 1 25 doi 10.1080 02724634.1997.10010948 ref Apedolepis is a genus of prehistoric jawless fish which lived during the Ordovician period . The type specimen is only a derman scale CPC 33630 which discovered in Areyonga Creek, Gardiner Range, Central Australia , and referred by paleontologist Gavin C. Young in 1997. References reflist portal Paleontology paleo stub paleo fish stub Category Prehistoric fish Category Ordovician fish ... more details
italic title Taxobox name Bolboporites fossil range Ordovician image Bolboporites top view.jpg image caption Bolboporites top view Middle Ordovician, Russia image2 caption Bolboporites side view Middle Ordovician, Russia image2 Bolboporites side view.jpg regnum Animal ia phylum Echinoderm ata subphylum Blastozoa classis Eocrinoidea ordo familia genus Bolboporites genus authority subdivision ranks Species subdivision portal Paleontology Bolboporites is an extinct genus of conical echinoderm that lived in the Ordovician of Europe and North America . They are interpreted to have lived on the seafloor with the pointed end of the cone down in the sediment and the broad end upwards. A single brachiole extended from a hole in this top surface and bent into the current like the arms of crinoids Rozhnov and Kushlina, 1994 . It is likely an eocrinoid which diversified in the Baltic region and then migrated to North America Rozhnov, 2009 . References Rozhnov, S.V. 2009. Eocrinoids and paracrinoids of the Baltic Ordovician basin a biogeographical report. IGCP Meeting, Ordovician palaeogeography and palaeoclimate, Copenhagen, p. 16. Rozhnov, S.V. and Kushlina, V.B. 1994. Interpretation of new data on Bolboporites Pander, 1830 Echinodermata Ordovician , p. 179 180, in David, B., Guille, A., F ral, J. P. & Roux, M. eds. , Echinoderms through time Balkema, Rotterdam . paleo echinoderm stub Paleo stub Category Echinoderms ... more details
Italic title Taxobox name Pliomerina fossil range fossil range Middle Ordovician Late Ordovician Middle Late Ordovician regnum Animal ia phylum Arthropod a classis Trilobite Trilobita ordo Phacopida familia Pliomeridae genus Pliomerina genus authority Chugaeva, 1958  ref cite journal author Gregory D. Edgecombe, Brian D. E. Chatterton, Beatriz G. Waisfeld and Norberto E. Vaccari year 1999 title Ordovician pliomerid and prosopiscid trilobites from Argentina journal Journal of Paleontology volume 73 issue 6 pages 1144 1154 jstor 1306825 ref Pliomerina is a genus of trilobite s. A new species, P. tashanensis , was described from the late Ordovician of China by Dong Chan Lee in 2012. ref name Xiazhenformation Cite journal author Dong Chan Lee year 2012 title Late Ordovician trilobites from the Xiazhen Formation in Zhuzhai, Jiangxi Province, China journal Acta Palaeontologica Polonica volume issue in press pages url http app.pan.pl article item app20100036.html doi 10.4202 app.2010.0036 ref References Reflist 32em Category Phacopida Category Ordovician trilobites Trilobite stub ... more details
Automatic taxobox fossil range Fossil range Middle Ordovician Early Devonian image image width image caption authority Eichwald 1860 Castelloceras is an extinct genus of actively mobile carnivorous cephalapod of the family biology family Baltoceratidae that lived in what would be Europe during the Ordovician from 468 443.7 Annum mya , existing for approximately Mya 468 443.7 million years . ref http paleodb.org cgi bin bridge.pl?action checkTaxonInfo&taxon no 142795&is real user 1 PaleoBiology Database Castelloceras , basic info ref Taxonomy Castelloceras was named by Evans 2005 . Its type is Castelloceras arennigense . It was assigned to Baltoceratidae by Evans 2005 . ref D. H. Evans. 2005. The Lower and Middle Ordovician cephalopod faunas of England and Wales. Monograph of the Palaeontographical Society 623 1 81 ref Sources reflist Fossils Smithsonian Handbooks by David Ward Category Cephalopods Category Ordovician animals Category Ordovician extinctions Category Prehistoric animals of Europe portal Paleontology ... more details
Automatic taxobox fossil range Ordovician authority Chen 1974 subdivision ranks Species subdivision Eosomichelinoceras is an extinct genus from the actively mobile carnivorous cephalapod family biology family Baltoceratidae that lived in what would be Asia and South America during the Ordovician from 468 449 Annum mya , existing for approximately Mya 468 449 million years . Taxonomy Eosomichelinoceras was named by Chen 1974 . ref http paleodb.org cgi bin bridge.pl?action checkTaxonInfo&taxon no 12497&is real user 1 PaleoBiology Database Eosomichelinoceras , basic info ref Its type is Eosomichelinoceras huananense . It was assigned to Orthocerida by Chen 1974 and to Baltoceratidae by Kr ger et al. 2007 . ref J. Y. Chen. 1974. Ordovician Nautiloidea. A Handbook of the Stratigraphy and Paleontology in Southwest China 138 143 ref Morphology Eosomichelinoceras is a smooth or transversally lirate slender, orthoconic Baltoceratidae baltoceratid with a narrow, tubular siphuncle ref B. Kr ger, M. S. Beresi, and E. Landing. 2007. Early orthoceratoid cephalopods from the Argentine Precordillera Lower Middle Ordovician . Journal of Paleontology 81 6 1266 1283 http findarticles.com p articles mi qa3790 is 200711 ai n21137444 pg ref located between the center and the edge of the shell. Connecting rings are thin, septal necks orthochoantic, and without known endosiphuncular or cameral deposits. References reflist Fossils Smithsonian Handbooks by David Ward Category Cephalopods Category Ordovician animals Category Ordovician extinctions Category Prehistoric animals of North America Category Prehistoric animals of Asia portal Paleontology ... more details
Taxobox name Troedssonellidae fossil range L Ordovician Ord Cassinian M Ordovician Ord Whiterock Stage Whiterockian image regnum Animalia phylum Mollusca classis Cephalopoda subclassis Nautiloidea ordo Orthocerida or Dissidocerida familia Troedssonellidae genus familia authority Kobayashi 1935 Troedssonellidae is a family of Orthocerida orthoceroid cephalopods from the Ordovician , derived from rod bearing Baltoceratidae , that have a continuous lining within the siphuncle that resembles very thin and slender endocones. Shells are generally slender and orthoconic. The siphuncle is central or subcentral, composed of straight or slightly expanded segments. Septal necks generally short and connecting rings are thin. Thin cameral deposits lining the chambers are known, which along with the position of the siphuncle and thin connecting rings distinguishes them from the Endocerida endocerids in which they have been included. ref Sweet 1964 Nautiloidea Orthocerida in the Treatise on Invertebrate Paleontology , Part K, Teichert and Moore eds ref ref name Flower Flower 1976. Ordovician Cephalopod Faunas and Their Role in Correlation, in The Ordovician System proceedings of a Palaeontological Association symposium, Sept 1974 ref Troedsonnellids first appear high in Lower Ordovician Cassinian strata, beginning with Tajaroceras and extend at least through the Whiterock Stage of the Middle Ordovician. ref name Flower ref Hook and Flower 1977. Late Canadian Zones J,K Cephalopod Faunas from Southwestern United States Memoir 32, New Mexico Bureau of Mines and Mineral Resources. ref They also may have given rise to the Striatoceratidae and to the Narthecoceratidae of the Middle and Late Ordovician. ref name Flower Gerera include Tajaroceras , Buttsoceras , Oxfordoceras , Ctenoceras , Troedsonnella and the possible Glenisteroceras and Wolungoceras References Reflist Category Nautiloids ... more details
automatic taxobox fossil range geo range Ordovician ref ref name vanBelle1981 authority Bergenhayn, 1955 Septemchiton is an extinct taxon rank of chiton polyplacophoran mollusc . Septemchiton became extinct during the Ordovician period. ref name vanBelle1981 Fossil chiton catalogue ref References reflist Category Paleontology Category Chitons Category Taxonomy paleo mollusc stub ... more details