A couple weeks ago I purchased the
H. severus that Sencion88 was selling in the Marketplace. He says it's female but my first thought was male. At any rate, it is the most pushy, aggressive severum I have ever owned.

It quickly dominated my quarantine tank and has put my large angelfish and my chocolate cichlid in their places. I'm almost afraid to put it into the 150 because most of the fish in there are smaller, in the 4 - 5" range.
Joel also sent another tiny severum in the box with her and she does not mess with him at all. He's the only fish in the tank that isn't being terrorized at the moment. I don't know how she'll react to my other severums if I introduce her to the 150. Maybe I'll just wait until my 220 is running...