The probiscisaurus is a descendant of the prosubigosaurus. It has gained a trunk, which it uses to reach the higher leaves of big plants like the shallowpalm. It still has camouflage, but the biggest difference from its ancestor is the brood care. The middle legs have only one function: they hold the egg until the young probiscisaurus hatches, and will then hold the young probiscisaurus as well. Because a probiscisaurus can hold only one egg, they only lay one each time. The probiscisaurus has an acromion of about 75 centimeters. It travels in small groups through the swamp and the southern part of the forest.