I have a coastal that looks similar to that. I also have a diamond X jungle that looks close to it. It could also very well be a pure jungle or a jungle X coastal. Who did you get it from, and did you see the parents?
If you can't trace back the parents, I would just be honest about not knowing the parentage when you breed it. Of course, the question would then be what do you breed it to? It's a pretty snake, though.