This Specimen has been sold.
Rare, 2.45" Spathacalymene Trilobite - Indiana
This is an good-sized, 2.45" long specimen of a rare Silurian trilobite from the Osgood Formation in Indiana, Spathacalymene nasuta. This trilobite has a distinctive snout projection off the front of the glabella that may have been used to stir up sediment for feeding. These trilobites are very hard to find complete and this one is quite a bit larger than average size. There is some restoration to the front of the rostrum.
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 currently described species, filling nearly every evolutionary niche. Due in large part to a hard exoskeleton (shell), they left an excellent fossil record.