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Ancient Sharks Likely More Diverse Than Previously Thought（图）
Ancient Sharks More Diverse Previously Thought
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2018/1/31
Sharks have a reputation as ravenous hunters and apex predators, but new analysis of fossil records shows that some of the earliest sharks might have been filter feeders, taking in water through their...
Contribution of Eocene sharks and rays from southern France to the history of deep-sea selachians
SW France Eocene Deep-sea selachians Fossil record
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2009/10/20
Fossil deep-sea selachians are rare and their diversity underestimated as a consequence of the scarcity of available outcrops of sediments containing them. Here we report a new fossil locality from th...
Anew species of extinct bullhead sharks,Paracestracion viohli sp. nov.(Neoselachii, Heterodontiformes),from the Upper Jurassic of South Germany
Heterodontidae Late Jurassic Schamhaupten Diversity
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2009/10/20
The early history of heterodontid sharks is documented mainly by isolated teeth. So far, three different heterodontid genera have been recorded from the Jurassic: Proheterodontus from theMiddle Jurass...
Interrelationships of Mesozoic hybodont sharks as indicated by dental morphology preliminary results
Hybodont sharks Tooth morphology Dentition Mesozoic Phylogeny
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2009/10/20
As many hybodont sharks are known solely from their teeth, this investigation approaches the phylogeny of the group with an emphasis on tooth morphology and dentitional patterns. The preliminary resul...
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...
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...
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...
A new occurrence of sharks in the Menilite Formation (Lower Oligocene) from the Outer (Flysch) Carpathians of Poland
Hexanchoid sharks “Notidanus” Heptranchias Menilite shales/Formation Outer Carpathians
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2009/10/20
Bieńkowska-wasiluk, M. and radwański, A. 2009. A new occurrence of sharks in the Menilite Formation (Lower Oligocene) from the Outer (Flysch) Carpathians of Poland. Acta Geologica Polonica, 59 (2), 23...