Belemnites (family)

Belemnites are an extinct group of marine cephalopods, closely related to modern squids and octopuses, that thrived from the Late Paleozoic to the end of the Cretaceous period. They had elongated bodies and a bullet-shaped internal shell, resembling a dart, which is the most commonly found fossil of this group. Belemnites inhabited oceans and were agile predators. Their fossils provide important insights into ancient marine environments and the evolutionary history of mollusks. Due to their distinctive shape and abundance in certain rock layers, they are often used by geologists as marker fossils for dating sedimentary rocks.