Trilobites exemplify the diverse nature of prehistoric aquatic life. This class of arthropods formed a staggering amount of different species throughout the Cambrian period. Today, over 5,000 different genera of trilobites have been discovered and named, with more surely waiting to be discovered.

These specimen are Elrathia kingii, perhaps the most iconic and well known trilobite species among the thousands on record.

This particular fossil comes from Utah's Wheeler Shale Formation, a prolific trilobite fossil source that's unveiled dozens of new species since its discovery. More than any other, the iconic E. kingii has defined what we think of as the look of a trilobite, with its neat spines and clearly segmented body.

Each trilobite fossil plate is a unique item and are sold individually by size. Each ships in a sturdy shipping container along with a certificate of authenticity and a metal display stand. You can find all of our current trilobites in the collection below.

Oceans cover about three quarters of our planet, but much of them remain unexplored and unknown to us. It is here in this mysterious environment that life on Earth first began. Forms were simple at first, with plant life and multicellar organisms only just emerging in complexity.

Then, 540,000,000 years ago, the ocean was host to an incredible event that would change the course of evolution forever: the Cambrian Explosion. This massive acceleration of diverse life gave way to the swift radiation of new species and unique evolutionary traits. One creature that exemplified this principle of change so clearly was the trilobite.

This class of arthropods formed a staggering amount of different species throughout the Cambrian period. While all species shared some common aspects, each would evolve unique adaptations that set them apart. Today, over 5000 different genera of trilobites have been discovered and named, with more surely waiting to be discovered.

The common structure that all trilobites share is rather simple. They had a hard exoskeleton composed of three lobes: left, right, and center. Their bodies are also segmented into a cephalon (head), thorax (body), and pygidium (tail). From this base, trilobites evolved into a myriad of strange and unique forms. Some specimens have even been discovered with fossilized soft tissues such as legs, gills, and antennae, giving us a clearer picture of the trilobite’s form in life.

Despite certain commonalities, trilobite species were as varied as could be. Spiny exteriors were a common adaptation and were used by some species to ward off predators while others developed spines as a hunting tool. Compound eyes were found in many species, with some having enormous oculars giving them nearly 360-degree vision. Specialized exoskeleton articulation even allowed them to roll into a ball. Trilobites varied in size as well, from a mere tenth of an inch long to the massive 28-inch Isotelus rex.

Trilobites had an incredibly diverse amount of lifestyles to match their many variations in form. Fossils have been discovered in areas that would have been shallow basins of saltwater as well as the floors of ancient trenches. Ocean floor scavengers, predators, filter feeders, swarming schools, and even open water swimmers have all been suggested modes of survival of different groups. There is even evidence some species made short trips onto dry land.

Elrathia kingii is on of the most prolific specimens across the entire trilobite fossil record, with millions of remains unearthed from Utah's Wheeler Shale Formation. These fossils are so well preserved due to the surrounding rock matrix made of cone-in-cone calcite incrustation, which protected the inner fossil.

E. kingii's vast fossil record also owes itself to ecological niche, the trilobite thriving in low-oxygen waters where most creatures could not survive for long. A lack of scavengers kept their bodies in great condition and the low oxygen also supported preservation during the fossilization process.