Help with an African knife

[Gavin Nugent]

This is one of 2 African knives I have here. Overall this one is 52cms long in the scabbard and 49.5cms long without the scabbard. The images do speak better than what I could do to describe it. The pattern carved into the wood reminds me of a crocodile's back to some degree. The scabbard is 2 pieces of wood held together at the base by what I beleive looks like animal sinew. The reverse of the scabbard has no carving.
What is it, where did it come from and PM me if you can help with the question I am not supposed to ask here.

thanks

Gav