Just got a starter colony recently and when I popped the top there was a male(smaller and thinner) hooked up to a stark white, freshly molted female. She dragged him a way immediately, leaving me no time to get a pic. At first I thought it must be her shed skin, but they were butt to butt and he was desperately trying to hold on for dear life as she ran away with him attached. BTW, is it prosticus or posticus? I've seen it spelled both ways. It is spelled posticus in the Allpet Roaches book, but I usually see the r on this forum.

I would go by what is printed in the book

Many if not most roach species breed imediately upon the female maturing. It is pretty common to see a male or males swarming arounnewly molted/matured female. In Eublaberus sp. you almost always know when a female just molted into maturity as you will hear alot of scuttling around in the bin pretty much every time. In my E.distanti bin it is particularly odd because they move collectively in waves, like fans in a spots stadium doing the "wave" and it sound like a bin full of shifting rattlesnakes.... or over a thousand lightly armored individuals moving then standing still then moving again in rythmic succession.

But you get the idea....