Ammonite

Ammonite from the UCC fossils collection Ammonite from the UCC fossils collection

Ammonite from the National Museum NI fossil collection Ammonite from the National Museum NI fossil collection

Ammonite - Pachydiscus oldhami from the National Museum NI fossil collection Ammonite - Pachydiscus oldhami from the National Museum NI fossil collection

Ammonite - Paltechioceras from the National Museum NI fossil collection Ammonite - Paltechioceras from the National Museum NI fossil collection

How to recognise them

Spiral shell, narrow whorls.

Fossil Info

Ammonites are a type of cephalopod animal related to modern-day squid and octopus that lived from the Devonian Period around 400 million years ago but went extinct during the end-Cretaceous mass extinction event. They had large eyes for finding prey and many were built for speed, with hydrodynamic shells with tapered edges. Their shells have beautiful patterns made by the very complex sutures or joins between the body chambers in the shell. During growth, these animals compensated for the heavier shell by allowing gas to diffuse into the central body chambers through a tube called the siphuncle.

Fun Fact

Ammonites were once thought to be curled-up sea snakes!

Ireland's Fossil Heritage

Explore UCC