Dovii's by far are worst, other than them i say it's a throw up depending on induvidual fish, all have different attitudes and aggresion tendencies, one may say jaguar but being that they are so much more common than the rest that doesn't say alot. IME Male jaguars in a breeding pair, with newly hatched fry or new eggs are probably the most aggresive. but it's a throw up between, loiselli, mota's, freddies for second.
umbriferiums aren't classified under parachromis btw
My jag is extremely territorial during tank maintenance, he'll hit the python with such force that I'm always worried that he'll hurt himself. However he shows no aggression when I'm outside the box.
I have a tank with most of them except for a Dovii and the most aggressive one is the male Red Tiger Motaguense. Next would be the male Freddy, then male managuense. all the males are in the 11" - 13" mark