This Specimen has been sold.
1.85" Protolenus Trilobite Molt With Pos/Neg - Tinjdad, Morocco
This is an 1.85" long specimen of the Middle Cambrian trilobite Protolenus (Protolenus) densigranulatus. The bright orange coloration is natural and due to the oxidization of iron pyrite. This specimen is a molt. Comes with both the positive and negative impressions.
Trilobites were a very diverse group of extinct marine arthropods. They first appeared in the fossil record in the Early Cambrian (521 million years ago) and went extinct during the Permian mass extinction (250 million years ago). They were one of the most successful of the early animals on our planet with over 25k described species, filling nearly every evolutionary niche. Due in large part to a hard exoskeleton (shell), they left a excellent fossil record.