Trilobite Fossils | Darwin and Wallace: A Nature & Fossil Store

Trilobite Fossils


        Trilobites are the most recognized and proliferous arthropod fossils on the planet. To date, there are over 20,000 known species of trilobite, ranging from the smallest known genus, Peronopsis, at 0&5/16" long, to the largest known, Isotelus, at 28" long. They are known the world over, though their origin appears to come from Siberia, where the earliest trilobites on record date to approximately 540-520 million years ago during the Early Cambrian period. They are named for the "three lobes" that comprise the left, middle, and right segments of their bodies. Trilobites are noted for being exclusively marine creatures, with some possibly adapting into fresh water environments. Early on in their evolution, they would mostly consist of unimpressive, flat, pill bug-looking animals, however, with the development of trilobite-predators and adaptation into new environments, the trilobites would undergo a massive radiation of sizes and forms, including the first complex eyes, as well as spikes and spines for protection. The trilobites themselves were mostly feeding on nutrients from the marine floor or plankton, as well as hunting other similar sized creatures, depending on the species. Despite being one of the most successful groups of animals of all time, the trilobites would eventually become extinct at the end of the Permian period approximately 250 million years ago, ending their 270 million year existence. The first documented trilobites were described by Welsh naturalist Edward Lhwyd in 1698, which he believed to be the remains of a prehistoric flounder. It was realized soon after that these fossils were of creatures that had never been described before in science. In 1771, the term "Trilobite" was created to describe these fossils by German geologist Johann Ernst Immanuel Walch. Though these creatures were only then becoming a part of science, trilobites had actually been collected by people for thousands of years previous, and have even been discovered in human burial mounds dating to over 50,000 years ago.

Click on the images below to see the incredible fossils we offer in our trilobite selection: