Exceptionnelle plaque fossile présentant un groupe de trilobites après extinction simultanée Exceptional Trilobite Mass Mortality Plate Paradoxydes sp. Middle Cambrian Morocco Trilobites are among the most ancient creatures to have inhabited the planet, and are perhaps the most familiar fossils after those of the dinosaurs. They are a class of marine arachnomorph arthropods that inhabited the seas in multitudes during the Paleozoic Era, from the Cambrian through the Permian period. Inhabiting the oceans for over 300 million years, the last of them disappeared during the mass extinction approximately 250 million years ago—making them one of the most successful species to ever live. Paradoxides is a genus of large to very large trilobite found throughout the world. Its cephalon was semicircular with free cheeks ending in long, narrow, recurved spines. The eyes were crescent shaped and provided a 360° view. Its elongate thorax was composed of 19-21 segments and adorned with longish, recurved pleural spines. Certain examples of Paradoxydes sp. can be record-breaking in size. Such is probably the case with the present mass mortality plate of nearly 21 enormous trilobites, measuring up to 20 to 25 cm, which are original to their matrix. Measuring 185 x 125 x 7 cm For further information on this lot please visit Bonhams.com