I have had matings between two different species but it does not produce fertile ooths. But if you mated say S. Carolina and S. Californica that wil work as they're basically the same thing.
Oh... I thought somebody said that won't work too. Was it you, Yen?
It will work and I have pics to prove it. However it will not produce any offspring.
Oh... interesting. Okay.
I think Rick is saying the mantis (of different species) will mate, but it will not produce viable ootheca. Although rarely, mantis of the same genus but different species may cross breed and produce a new sterile generation (such as P. Wahlbergii x P. Ocellata, Sph. Lineola x Sph. Centralis, etc).