Aulacostephanus

Aulacostephanus
Temporal range: Tithonian
Aulacostephanidae - Aulacostephanus yo.JPG
Fossil shell of Aulacostephanus yo from France, on display at Galerie de paléontologie et d'anatomie comparée in Paris
Scientific classification
Kingdom:
Phylum:
Class:
Subclass:
Order:
Family:
Genus:
Aulacostephanus

Aulacostephanus is an extinct ammonoid cephalopod genus from the Upper Jurassic Tithonian belonging to the perisphinctacean family Aulacostephanidae.

Aulacostephanus produced a discoidal, strongly ribbed, evolute shell of moderate size, reaching diameters of 16 cm (~6.5in.), or so. Ribs diverge in pairs and threes from nodes on the umbilical shoulder and extend radially outward onto the ventro-lateral shoulder, but do not cross the venter, (the outer rim). Sides are flat, the venter steeply rounded, with an open bend or median groove running down the middle.

Clutches of eggs attributed to this genus have been discovered in the Kimmeridge Clay.

Distribution

Jurassic sediments of Germany, the Russian Federation, Switzerland and the United Kingdom



This page was last updated at 2022-01-03 09:07 UTC. Update now. View original page.

All our content comes from Wikipedia and under the Creative Commons Attribution-ShareAlike License.


Top

If mathematical, chemical, physical and other formulas are not displayed correctly on this page, please useFirefox or Safari