Olenellus gilberti
Trilobite
Early Cambrian
Pioche Formation: C-Shale
Pioche, Lincoln County, Nevada, USA

Large, high quality 40mm trilobite on 134mm slab. Outstanding example of this classic trilobite.

Olenellus is a genus of extinct trilobites that lived during the Early Cambrian period, approximately 530-520 million years ago. It was one of the first trilobites to evolve and is known from a wide variety of locations around the world, including North America, Greenland, and Siberia.

Olenellus is characterized by its distinctive elongated body, which is divided into three main parts: the head, or cephalon; the thorax, which contains a series of segments with legs or appendages; and the pygidium, or tail.

One of the notable features of Olenellus is its eyes, which are among the earliest known examples of compound eyes in the fossil record. The eyes of Olenellus were large and positioned on the sides of the head, providing a wide field of vision. This adaptation likely helped Olenellus to locate prey and avoid predators in its marine environment.

Olenellus is also important from a stratigraphic standpoint, as it is used as a key index fossil for the lower Cambrian period. The presence or absence of Olenellus fossils can help geologists to date rocks and correlate strata across different regions.