Hi
Ian,
Is your total skull length the
basal length from incisors to foramen magnum? If so, it is (as you say) too
large for leopard and also jaguar. It's lion or tiger sized. The criteria for
distinguishing between them was published by Boule in 1906, and similar criteria
(including translations of Boule) are given in Merriam & Stock's
discussion of the Rancho La Brea Felids. The inferior border of the
mandible is a good diagnostic indicator - but not infallible - in a sample
of 30 lions I found one with a straight ramus. The shape of the nasals are
also a good indicator, but easier to see on the diagrams than to describe.
Merriam, J. C. & Stock, C. (1932) The Felidae of Rancho la Brea
Publication 422. Washington DC: Carnegie
Institute.
Boule, M. (1906) Les grands chats des cavernes.
Annales de paleontologie 1, 69 - 95.
Cheers,
Hannah.