The laws of taxonomy do not seem to apply to many snakes!
Recently, members of genus Lampropeltis (king and milk snakes),
Elaphae (rat snakes) and Pituophis (pine , bull, gopher snakes)
have been found fully able to breed with one another and create FERILE young.
The breeders who do it have to "trick" the snakes into breeding.
Example: A breeder has a pair of corn snakes and a female kingsnake. He takes the fheshly shed skin of the ovulating female corn and mixes it with some water in a blender. Then takes the female king and sprays her with the "love potion" and puts her with the male corn...who believes her to be a female corn and breeds her.
There are now integrates betwwen all types of rat, king, and gopher/pine snakes.
Personally...I find these animals much LESS interesting as man made hybrids than the naturally occuring snakes...but...just check out the "hybrid" forum and you'll se what I mean!