Hi Detlef, I also find this a quite interesting knife (because of the handle and age). The mouth seems to represent more a dragon, the ears (??) look like switches, and there are other ribboned horns coming from under and than there is (another) 'medallion'!!
Perhaps it is the fact that it is up to the creator to define how a dragon looks like?!?! Age; 1870's to my estimate.
The medaillion etc do remind me of characteristics of kampilans.
Anyone ?