Lower cretaceous ammonites from the neuquén basin argentina: The hauterivian neocomitid genus hoplitocrioceras(giovine 1950)
Hoplitocrioceras is a poorly-known ammonite genus of late Early Hauterivian age that may be endemic to the Neuquén Basin Argentina where it occurs at a clearly defined horizon in the Agrio Formation. It is an unusual genus with uncoiling (crioceratitid) whorls that remain linked by a thick dorsal sh...
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Autores principales: | , |
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Formato: | JOUR |
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Acceso en línea: | http://hdl.handle.net/20.500.12110/paper_01956671_v22_n2_p201_AguirreUrreta |
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Sumario: | Hoplitocrioceras is a poorly-known ammonite genus of late Early Hauterivian age that may be endemic to the Neuquén Basin Argentina where it occurs at a clearly defined horizon in the Agrio Formation. It is an unusual genus with uncoiling (crioceratitid) whorls that remain linked by a thick dorsal shell that drapes over the tips of sharp upwardly-pointing ventro-lateral spines. It has been interpreted as either a necomitis or a crioceratitid but is here regarded as one of the last members of the Family Neocomitidae. One new species is proposed: H. giovinei. © 2001 Academic Press. |
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