Their patterns are different as well most of the time.... but I can't really go through and tell you all of the differences in pattern between the two, because each animal is different. Your best bet is to look directly at the eyes first thing, because it's a dead give away. From there, start noticing the patterns that each animal you're seeing has, and if it's a henkeli, or a fimbriatus. Once you've seen 15-20 specimens of each, in both sexes, you can start to get a good idea of the pattern differences between the two species.