Spitidiscus


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

Species

List of species within Spitidiscus:Spitidiscus hugiiSpitidiscus kilapiae Rawson and Aguirre-Urreta, 2012 - ArgentinaSpitidiscus oregonensis Imlay, 1960 - OregonSpitidiscus riccardii Leanza, and Wiedmann, 1992 - ArgentinaSpitidiscus rotulia - EnglandSpitidiscus simitiensis Haas, 1960 - Colombia
  • ''Spitidiscus vandeckii''

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.

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: