Asaphida
Another kind of trilobite, but way different than the traditional trilobite. Although also a bottom dweller, this species seemed to get around more since it was smaller in size and eventually adapted eye stalks (you can see them growing in the picture). They too fed on food particles and could burrow. They had about 5-12 Thorax segments and an exoskeleton, with the only difference being the size and eye stalks. They survived the Ordovician period and the mass extinction but did not survive the Silurian period.