Spitidiscus seunesi (Kilian) Barremian, Brestak, Cr1 426X1 (Coll. St. Breskovski) at the Sofia University Museum of Paleontology and Historical Geology

Spitidiscus is a genus of ammonites placed in the family Holcodiscidae.

Species

List of species within Spitidiscus:

  • Spitidiscus hugii[citation needed]
  • Spitidiscus kilapiae Rawson and Aguirre-Urreta, 2012 - Argentina
  • Spitidiscus oregonensis Imlay, 1960 - Oregon
  • Spitidiscus riccardii Leanza, and Wiedmann, 1992 - Argentina
  • Spitidiscus rotulia - England[citation needed]
  • Spitidiscus simitiensis Haas, 1960 - Colombia
  • Spitidiscus vandeckii (d'Orbigny, 1847)

Description

Member species have a rather evolute shell in which the whorl section is more or less circular, venter broadly rounded and dorsum fairly deeply impressed. Close, fine low, single or rarely branching ribs are interspersed by frequent straight or slightly sinuous, moderately deep but wide constrictions. The type species S. rotulia is from the Hauterivian of England.[citation needed]

Biostratigraphic significance

The first appearance of the species Spitidiscus hugii or Spitidiscus vandeckii are proposed to be the marker for the beginning of the Barremian.

Distribution

Spitidiscus has been found in:

  • Agrio Formation, Argentina
  • Magdalena Valley, Simití and Cáqueza, Colombia
  • Kaliste Formation, Czech Republic
  • France
  • Gagra, Georgia, Caucasus
  • Maiolica Formation, Italy
  • Subbetics, Spain
  • Foggy Creek, Oregon
  • Bulgaria[citation needed]
  • Portugal[citation needed]
  • Russia[citation needed]
  • Morocco[citation needed]
  • Mexico[citation needed]

Bibliography

  • . Paleobiology Database.
  • . Encyclopedia of Life (EOL).
  • Wright, Claud William; with John Hannes Callomon and M.K. Howarth (1996). Roger L. Kaesler (ed.). . Boulder, Colorado and Lawrence, Kansas: The Geological Society of America & University of Kansas Press. p..{{cite book}}: CS1 maint: multiple names: authors list (link)
  • Arkell, W. J.; Furnish, W. M.; Kummel, Bernhard; Miller, A.K.; Moore, R.C.; Schindewolf, O.H. (1957). "Part L, Mollusca 4: Cephalopoda, Ammonoidea". In Raymond C. Moore (ed.). . Geological Society of America and University of Kansas Press. p.. ISBN978-0-8137-3012-7 – via Internet Archive.{{cite book}}:ISBN / Date incompatibility (help)