Holcodiscidae
Holcodiscidae is an ammonite family placed in the superfamily Desmoceratoidea.
Description
Moderately involute with rounded, rectangular, or depressed whorl section; straight or sinuous, fine, dense ribs typically continuing over venter and may be periodically truncated by oblique, enlarged ribs, with or without umbilical, lateral and ventrolateral tubercles. Suture rather simple.Genera
- Astieridiscus
- Holcodiscus
- Jeanthieuloyites
- Parasaynoceras
- ''Spitidiscus''
Distribution