That is Erythrinus sp. peru. I have a large 8"er. They are more timid than the rainbow wolf, Erythrinus erythrinus and can be kept with any fish not small enough to swallow. I have kept mine with all sorts of stuff with no territorial aggresion at all, including a Jag cichlid. In fact I would be more concerned about the Jag having the upper hand. Them and the rainbow tend only to be a problem when kept with other wolves and tend to ignore other fish to big to eat. There are of cause exceptions and I am speaking from my own personal expearence.
The next step is the Hoplerythrinus, orange wolf which will get a bit bigger, about 16", more likely 12" in captivity, It is a great open water swimmer and again can be kept with fish large enough not to eat.
The next group are Hoplias, There are a few of these ranging in size from 12" for Microlepis to potencialy 4' for Aimara. You can't really keep any of these with other fish. Some people have done it but the majority of the time it doesn't work out.