Skeledirge is based, at least partially, on Ammut, an Egyptian goddess of death. The bird on its head is an Egyptian plover, which pretty firmly establishes Skeledirge as a Nile crocodile.

Ammut was portrayed as a crocodile with a lion's mane (hence the fire "hair") who lived in a lake of fire, devoured the hearts of the unjust dead, and supposedly came up from the underworld to sun herself on the bank of the Nile.

Maybe a bit odd for one of the starters in the Spanish region to be Egyptian, but we already have the psychic dung beetle/scarab and the Cleopatra ostrich, so it fits right in