Eastern Quolls (Dasyurus viverrinus) normal and black form

Are these simply a melanistic form or are they a sub-species does anyone know ?

Just a dark morph I believe - as far as the animals that have been breeding in European collections over the past few years go, both morphs are known to pop up in the same litters, with 75% of animals representing the brown morph and 25% the dark morph. The latter are not truly melanistic, as the white spotting is retained.

yep, just a colour form not a separate subspecies.