The name 'Belemnite' pronounced 'BEL-EM-NIGHT' is derived from the Greek word belemnon which means javelin or dart due to that resemblance in the shape of the fossil. It was a common folklore tale that belemnites were formed from the strike point of lightning bolts into the ground; hence they are frequently referred to as 'thunderbolts' In several of the local dialects, belemnites are known to have been called "thunderbolts", "thunder-arrows", or sometimes even "Devil's Fingers" or "St. Peter's Fingers".
Belemnites roamed the oceans of the world between 65 and 210 million years ago. They strongly resembled their living relatives of today, the squid and the cuttlefish right down to the ink sack and 10 tentacles, theirs had hooks instead of suckers. It is currently believed that they evolved from the same ancestors as the ammonites. The belemnites became extinct about the same time that the majority of the dinosaurs disappeared.
Belemnites were believed to be efficient carnivores that caught small fish and marine animals with their tentacles, and then ate them with their beak-like jaws. It is believed that belemnites were built for speed and that they probably lived in shoals. Fossil evidence has shown that they formed a major part of the diet of Ichthyosaurs.
The 'guard' is the part of the belemnite that is normally found as a fossil. Sometimes a fossil is found with part of the phragmacone attached. Very rarely, part of the pro-ostracum is found fossilized.
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