Periplaneta question


Old Timer
Sep 1, 2007
I just got a nice sized order of Periplaneta americana in today and I noticed a few of them are quite dark. Does anyone know a better way than color variation to tell the difference between Periplaneta americana, fuliginosa, and brunnea? It would be great if a few P. brunnea or fuliginosa snuck their way into this shipment because they are much harder to find. Any help would be appreciated but either way, yay new roaches! :)

The group:

A comparison of the two side by side, one certainly P.americana, the other...??? (sorry for this poor shot, the plastic wasn't clear)

Another shot of one of the oddballs:

Last one: