Thanks! I'll try to find that publication! In case it is rhenana, it should be Metacervoceros, if we agree to follow Roman Croiter, otherwise simply Cervus. The Rusa option is a favourite of Carmelo Petronio, mainly (or only?) based on antler morphology. He also suggested Rusa for the Cretan Pleistocene deer. If peloponnesiacus is close to the ancestry of the latter, the circle is round.
I have no idea what is "Cervus peloponnesiacus", but I am curious to know it. Do you have an original published description of its remains and a figure of type material?
no, only fragmentary materials are known, and to my knowledge, practically nothing was described, other than by Sickenberg 1975, and the only complete antler from Megalopolis that was preserved (but never depicted / described!), has recently been destroyed during the June 2017 earthquake on Lesvos, unfortunately (the museum was damaged).