Yellow is a morph of the Armadillidium maculatum Zebra. AKA Yellow Zebra Isopod due to its bold yellow and brown/black stripes.
An active surface isopod that thrives in temperate environments supported by a moisture gradient. Keep one side moist to maintain humidity. Good ventilation is important.
Not fast-moving and not sexually dimorphic. 
AKA "Pill Bug", thus rolls into a ball to retain moisture when the habitat is too dry, as well as a defensive posture.