SOME LESSER KNOWN FEATURES OF THE ANCIENT CEPHALOPOD ORDER ELLESMEROCERIDA (NAUTILOIDEA, CEPHALOPODA)

@article{Krger2007SOMELK,
  title={SOME LESSER KNOWN FEATURES OF THE ANCIENT CEPHALOPOD ORDER ELLESMEROCERIDA (NAUTILOIDEA, CEPHALOPODA)},
  author={Bj{\"o}rn Kr{\"o}ger},
  journal={Palaeontology},
  year={2007},
  volume={50}
}
  • B. Kröger
  • Published 1 May 2007
  • Environmental Science, Geography
  • Palaeontology
Abstract:  Three specimens of the small breviconic ellesmeroceratid Paradakeoceras minor Flower, 1964 from the Tremadocian of the New York area preserve the annular elevation and muscle scars in moulds of the body chamber. The annular elevation is positioned at the base of the body chamber and is wider on the convex side of the shell than on the concave side. Multiple paired muscle scars can be seen within this annular elevation. A well‐preserved body chamber of the breviconic ellesmeroceratid… 
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  • J. Dzik
  • Geography, Environmental Science
  • 2010
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The morphology of the tentacles and fins are revised, and mouthparts and phosphatized gills are described for the first time, and a mathematical analysis supports the presence of the earliest known camera-type eyes, and fluid mechanical considerations suggest that the funnel is optimized for efficient jet propulsion in a low Reynolds number flow regime.
Conch structures, soft-tissue imprints and taphonomy of the Middle Ordovician cephalopod Tragoceras falcatum from Estonia
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The connecting ring structure is studied in the discosorids Phragmoceras and Trimeroceras, as well as in the ascocerid Choanoceras. These taxa have the Nautilus type of connecting rings, composed of
Characterization of nautiloid orders Ellesmerocerida, Oncocerida, Tarphycerida, Discosorida and Ascocerida: new superorder Multiceratoidea
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Cephalopod origin and evolution: A congruent picture emerging from fossils, development and molecules
  • B. Kröger, J. Vinther, D. Fuchs
  • Geography, Environmental Science
    BioEssays : news and reviews in molecular, cellular and developmental biology
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  • H. Mutvei
  • Geography, Environmental Science
  • 2020
ABSTRACT The sub-class Nautiloidea is divided into two super-orders, Nautilosiphonata and Calciosiphonata, based on different structural types of the connecting rings. The late Cambrian order
High-level classification of the nautiloid cephalopods: a proposal for the revision of the Treatise Part K
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The scheme proposed here utilizes the form of muscle attachment scars as a diagnostic feature at subclass level; other features (including siphuncular structures and cameral deposits) are employed at ordinal level; this scheme has the advantage of relative simplicity and presents a balanced approach which reflects the considerable morphological diversity and phylogenetic longevity of the nautiloid cephalopods.
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