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