It seems a new type of cockroach might have been discovered in a new york apartment. Mutation, very-shy-hidden-for-ages-type, I have no idea but, according to the article:

"[Closely-related] species don't differ [by] more than one percent, [while] this cockroach is four percent different, (...) This suggests it is a new species of cockroach."

So there you have it. If it's indeed a case of mutation (think pollution) I wonder how long until we start growing extra limbs...