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Mesozoic hybodont sharks from Asia and their relationships to the genus Ptychodus
Jurassic Cretaceous Hybodontiformes Ptychodontidae Asia
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2009/10/20
The affinities of the selachian genus Ptychodus is discussed and Hemiptychodus is here re-introduced as a subgenus characterized by unusual tooth ornamentation pattern.An overview ofAsian hybodont gen...
Ctenacanthiform Cladodont Teeth from the Lower PermianWichita Group,Texas,U.S.A.
Ctenacanthiform shark teeth Lower Permian Artinskian Texas USA
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2009/10/20
Isolated teeth of Glikmanius occidentalis occur in ten vertebrate faunas in theWaggoner Ranch Formation and in one fauna in the underlying Petrolia Formation. They range in size (anteromedial-posterol...
Systematics and dental system reconstruction of the durophagous chondrichthyan Lagarodus JAEKEL,1898
Chondrichthyans Lagarodus Carboniferous Systematics Dental system
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2009/10/20
The type species of the Carboniferous chondrichthyan genus Lagarodus JAEKEL, 1898 is changed to Psammodus specularis TRAUTSCHOLD, 1874 because of an identification error in TRAUTSCHOLD (1874). Five mo...
New chondrichthyan teeth from the Early Carboniferous of Britain and Russia
Viséan-Serpukhovian Carboniferous Anachronistidae Ginteria gen.nov.
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2009/10/20
Ginteria fungiforma gen. et sp. nov. is described on the basis of isolated teeth from the Viséan (Brigantian) of the Matlock Limestone Formation of Derbyshire, England and the Late Viséan (Msta Format...
Some observations on Denaea fournieri (Chondrichthyes,Symmoriiformes) from the Lower Carboniferous of Belgium
Denaea Symmoriiformes Chondrichthyes Lower Carboniferous
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2009/10/20
Preliminary observations are presented concerning endoskeletal morphology in the Lower Carboniferous symmoriiform shark Denaea fournieri, and some problems in the original description are highlighted....
Carcharopsis prototypus and the adaptations of single crystallite enameloid in cutting dentitions
Carcharopsis Priohybodus Thaiodus Carboniferous Enameloid ultrastructure
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2009/10/20
Carcharopsis is a Palaeozoic shark comprising an enameloid-covered cutting dentition comprising serrated teeth.The enameloid ultrastructure of the teeth of C. prototypus is examined for the first time...
Early Frasnian sharks from central Iran
Chondrichthyes Teeth Scales Omalodontiformes Phoebodontiformes
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2009/10/20
Two limestone bone-beds in the early Frasnian of the Chahriseh section, central Iran, yielded numerous chondrichthyan teeth and scales. The fauna includes, most probably, only two taxa: a hitherto unk...
New data on chondrichthyan microremains from the Givetian of the Renanue section in the Aragonian Pyrenees (Spain)
Chondrichthyans Taxonomy Devonian Givetian Pyrenees
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2009/10/20
The continued investigations on the Middle Devonian part (Givetian, Middle through Upper Polygnathus varcus conodont Zones) of the section near the Renanué village in the Aragonian Pyrenees, Spain, br...
New information on the Devonian shark Mcmurdodus,based on material from western Queensland,Australia
Mcmurdodus Devonian Hexanchiformes Echinorhinus Prismatic calcified cartilage
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2009/10/20
Histological structure of the type and newly collected teeth of the shark Mcmurdodus whitei TURNER &YOUNG,1987, from a Devonian (?late Emsian-early Eifelian) limestone outcrop in the Cravens Peak Beds...
Devonian filter-feeding sharks
Chondrichthyes Teeth Devonian Frasnian Utah Nevada
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2009/10/20
Upper Frasnian rocks of Utah and Nevada yielded several multicuspid, low-crowned shark teeth. It is proposed that they were used mainly for filtering food from water. Two new chondrichthyan species be...
Protodus jexi Woodward,1892 (Chondrichthyes),from the Lower Devonian Campbellton Formation,New Brunswick,Canada
Early gnathostomes Early chondrichthyans Protodus Teeth Early Devonian
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2009/10/20
Protodus jexi from the early Emsian ‘Atholville beds’, Campbellton Formation between Atholville and Campbellton,northern New Brunswick, Canada, is redescribed from material studied by R. H. Traquair a...
New genus of chondrichthyans from the Silurian-Devonian boundary deposits of Tuva (Russia)
Chondrichthyans Elegestolepids Silurian Devonian Tuva
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2009/10/20
The scales of T.schultzei display significant morphological variation and are characterized by a very fine, comparatively wide and flat crown with longitudinal ribs and a small and short neck. The gro...
Variation of the synarcual in the California Ray,Raja inornata (Elasmobranchii:Rajidae)
Fused anterior vertebrae Computed tomography
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2009/10/20
Seven juvenile specimens of Raja inornata were CT scanned and digitally modeled to examine the variation of synarcual morphology with changing size. The synarcual is a highly variable skeletal element...
Evolutionary divergence in the feeding mechanism of fishes
Elasmobranchii Teleostomi Suction feeding Jaw mechanism
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2009/10/20
After the divergence of chondrichthyans and teleostomes, the structure of the feeding apparatus also diverged.Hyoid morphology varies considerably among fossil and extant elasmobranchs and has been hy...
Early Pliocene heteropods and pteropods (Mollusca,Gastropoda) from SantaMaria Island (Azores,Portugal):systematics and biostratigraphic implications
Mollusca Heteropoda Pteropoda Pliocene Biostratigraphy Azores Northern Atlantic
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2009/10/20
Aholoplanktonic mollusc assemblage from Neogene sediments of theAzorean island SantaMaria is described and analysed to determine the age of the sediments. Sixteen taxa are documented (three heteropods...