I think you are confusing the individual lion's name, Menelik, with the term for black animals: melanistic (or a new term I saw in a newly published mammal book: melanic).
Perhaps black-maned lions. (To the best of my knowledge, and I am 98% certain on this, there are no confirmed reports, historical or modern, of a black lion).
Yes the both names are correct, buyt they are not black lions, but with black maned´s, In Ethiopia they bassically call them Black Lion! Also in some papers!
Remember the incident of the killing of the black lions at the Ethiopian Zoo!