Yup, a defensive bite. Only time I've ever been struck at by one of the girls is because I opened up the tub and started messing with stuff using quick movements without giving her any warning. Serket didn't even come close to hitting me, but I stopped moving and left my hand in sniff range until she figured out it was me and calmed down. If I had actually got tagged it would have been my fault for not thinking and scaring her.