P. eusebia grows up to long. It is a mantisshrimp of the spearertype, possessing raptorialclaws with nine or more teeth. It may be distinguished from the other species in its genus, P. enodis and P. horologii, by the number of epipods, and from Rissoides desmaresti by the number of spines on the last segment of the raptorialclaw, with R. desmaresti having only five.