Holcodiscus

Holcodiscus Temporal range: Cretaceous
Fossil shell of Holcodiscus fallax from Alpes-de-Haute-Provence, on display at Galerie de paléontologie et d'anatomie comparée in Paris
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Cephalopoda
Subclass:	†Ammonoidea
Order:	†Ammonitida
Family:	†Holcodiscidae
Genus:	†Holcodiscus Uhlig, 1882

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.

Gallery

• 
  Holcodiscus mediocostatus Tzankov, 1935, Barremian, Razgrad, Cr1 1716 (Coll. V. Tzankov) at the Sofia University Museum of Paleontology and Historical Geology

External links

• "Holcodiscus". mindat.org. Retrieved 30 December 2021.
• "Holcodiscus". Encyclopedia of Life (EOL). Retrieved 30 December 2021.
• Wright, Claud William; with John Hannes Callomon and M.K. Howarth (1996). Roger L. Kaesler (ed.). Mollusca 4 Revised, Cretaceous Ammonoidea in Treatise on Invertebrate Paleontology Part L. Boulder, Colorado and Lawrence, Kansas: The Geological Society of America & University of Kansas Press. p. 48.{{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.). Treatise on Invertebrate Paleontology. Geological Society of America and University of Kansas Press. p. L371. ISBN 978-0-8137-3012-7 – via Internet Archive. {{cite book}}: ISBN / Date incompatibility (help)