New Ordovician mitrates (Echinodermata, Stylophora) from the Ancenis Basin (South Armorican Domain, France): Palaeogeographic and palaeoenvironmental implications. - Archive ouverte HAL Access content directly
Conference Papers Year : 2010

New Ordovician mitrates (Echinodermata, Stylophora) from the Ancenis Basin (South Armorican Domain, France): Palaeogeographic and palaeoenvironmental implications.

Bertrand Lefebvre
Serge Régnault
  • Function : Author
H. Lardeux
  • Function : Author
J.P. Kundura
  • Function : Author
Philippe Roussel
  • Function : Author

Abstract

Fossil echinoderms are extremely rare in Ordovician deposits of the South Armorican Domain (SAD), a structurally complex area stacked to the Medio-North Armorican Domain during the Hercynian orogeny. Two new occurrences of mitrate stylophorans are documented in the eastern part of the SAD (Ancenis Basin). The youngest known specimen of Lagynocystis pyramidalis is described from the Schistes du Fresne Formation (Late Ordovician). Mitrocystites mitra is reported from the Pierre Meliere Formation (Middle Ordovician), and for the first time, outside of Bohemia. The presence of these two cool-adapted taxa (both abundant in the Prague Basin) in the Ancenis Basin does not necessarily imply any close palaeogeographic relationship between the SAD and Bohemia. It more likely results from the existence of relatively comparable, deep (outer shelf, slope), and dysoxic palaeoenvironmental conditions both in the Ancenis Basin and the eastern part of the Prague Basin.

Domains

Paleontology
No file

Dates and versions

hal-00521028 , version 1 (24-09-2010)

Identifiers

  • HAL Id : hal-00521028 , version 1

Cite

Bertrand Lefebvre, Serge Régnault, H. Lardeux, J.P. Kundura, Philippe Roussel. New Ordovician mitrates (Echinodermata, Stylophora) from the Ancenis Basin (South Armorican Domain, France): Palaeogeographic and palaeoenvironmental implications.. 12th International Echinoderm Conference, Aug 2006, Durham, United States. pp.37-44. ⟨hal-00521028⟩
55 View
0 Download

Share

Gmail Facebook X LinkedIn More