It lived during the middle of the Atdabanian or the early part of the Botomian stage,[1] which lasted from approximately 524 to 518.5 million years ago.

Lower Cambrian of Spain[3] and Southern Morocco (Daguinaspis and Resserops-zone near Amouslek, Ouijane and Tiout).

As with most early trilobites, Resserops has an almost flat exoskeleton, that is only thinly calcified, and has crescent-shaped eye ridges.

As a representative of the Redlichiina suborder, the headshield (or cephalon) has sutures where the exoskeleton ruptures to assist in moulting.

The thorax has 12 segments, the 9th segment (counted from the front) carries large spines at its tips, longer than the genal spines and longer than the thorax axis, extending about one pygidial length behind the body.