Holcodiscus

Holcodiscus is an extinct ammonite genus placed in the family Holcodiscidae. Species in this genus were fast-moving nektonic carnivores. The type species of the genus is Ammonites caillaudianus.

Description
Circular to rectangular whorl section; fine, low, straight or flexuous simple or branched ribs, periodically truncated by thin, high, enlarged ribs bearing lateral and ventrolateral tubercles; inner whorls tending to have depressed whorl section and to resemble Olcostephanus.

Species
Source:


 * Holcodiscus caillaudianus d'Orbigny 1850
 * Holcodiscus camelinus d'Orbigny 1850
 * Holcodiscus hauthali Paulcke 1907
 * Holcodiscus tenuistriatus Paulcke 1907

Distribution
Fossils of species within this genus have been found in the Cretaceous sediments of Austria, Bulgaria, Chile, Colombia, Czech Republic, Slovakia, France, Italy, Morocco, Spain and Russia.