- Tytuł:
- Soft-tissue attachments in orthocerid and bactritid cephalopods from the Early and Middle Devonian of Germany and Morocco
- Autorzy:
-
Kroger, B
Klug, C.
Mapes, R. - Powiązania:
- https://bibliotekanauki.pl/articles/20326.pdf
- Data publikacji:
- 2005
- Wydawca:
- Polska Akademia Nauk. Instytut Paleobiologii PAN
- Tematy:
-
Cephalopoda
Germany
Orthocerida
Emsian
Morocco
Middle Devonian
soft tissue attachment
Early Devonian
Bactritida
muscle scar
Eifelian
Devonian
cephalopod
paleontology - Opis:
- In the Early to Middle Devonian shale sequences of Germany and Morocco, pyritised and secondarily limonitised cephalopod remains are common. Details of the soft−tissue attachment structures are sometimes preserved on the internal moulds of the body chamber and phragmocone of these cephalopods. Some of the studied Orthocerida show a very faint annular elevation and a dorsal furrow. A few Bactritida show a distinctive annular elevation with two circular bands. The bands form a paired or threefold lobe at the dorsum of the shell. Morphological differences between Orthocerida and Bactritida suggest different soft part morphologies. A comparison of the attachment scars shows that the Bactritida are intermediate between the Orthocerida and ammonoids with regard to their muscle attachment scars. The shape of the muscle scars are interpreted as indication for a planktonic lifestyle in Orthocerida and a comparatively active, nektonic lifestyle in Bactritida and ammonoids. The new genus Acanthomichelinoceras is erected. Acanthomichelinoceras commutatum, Cycloceras sp., Bactrites gracile, Bactrites sp. A, Bactrites sp. B, and Bactrites sp. C are described.
- Źródło:
-
Acta Palaeontologica Polonica; 2005, 50, 2
0567-7920 - Pojawia się w:
- Acta Palaeontologica Polonica
- Dostawca treści:
- Biblioteka Nauki