Subduction Zone
Veteran Member
Ammonites are perhaps the most widely known fossil, possessing the typically ribbed spiral-form shell as pictured above. These creatures lived in the seas between 240 - 65 million years ago, when they became extinct along with the dinosaurs. The name 'ammonite' (usually lower-case) originates from the Greek Ram-horned god called Ammon. Ammonites belong to a group of predators known as cephalopods, which includes their living relatives the octopus, squid, cuttlefish and nautilus (see pictures below).
http://www.discoveringfossils.co.uk/ammonites.htm
That particular ammonite might have been from that time, but ammonites themselves are much older than that. They first appeared in the Devonian:
https://en.wikipedia.org/wiki/Ammonoidea
" The earliest ammonites appear during the Devonian, and the last species died out during the Cretaceous–Paleogene extinction event."
The source that I first used, a very amateur one that was based upon searching the image you presented without a link, led to the 450 million year old claim, which was a bit high. But yours is far too young.