http://forum.zoologist.ru/viewtopic.php?id=406&p=5 Горгопс отличался формой черепа ,особенно высотой глазниц ,антиквус был на 20 % больше линейно и раза в два тяжелее.
Well, the difference between modern hippo and H. antiquus was the size. In general, as far I know, the prehistoric hippos doesn't have great differences respecto to the modern species... probably a best choice for reconstruction could be a anthracotheriid, like Bothryogenys... Off course, is only an idea...
By the way Rom, very well done your new Apataelurus!