Separating the two are the frontal claws, eye distances and tarsal rake number on the front basitarsus. The eye convergence is less in interruptus. Upper distance being 65 to 75% of lower. In algidus Evans says it is 50% or less. 3 spines on algidus, and four on interrutus. P. algidus has bifid claws, and interruptus dentate. Only eye distance is visible here. Seems to favor interruptus. Tough call.

Color is useless in these two.

Thanks for your comments.