No, AbbeysDad, that wan't the point of my little jest. And Jeff, you are correct--but we now know why it is not nitrospira either.
The fact is, there are no nitrifying "bacteria" in our fish tanks, or rarely ever. The task is actually performed by thaumarchaeota, usually referred to as AOA (ammonia oxidation archaea), as opposed to the long-assumed AOB (ammonia oxidation bacteria).
Archaea were only discovered during the last decade (2008), so this is still a very new area. I was reminded of this yesterday when I came across a good article in the March (2013) issue of Practical Fishkeeping. I did actually mention this last year, here is that thread which contains a link to one scientific paper: http://www.tropicalfishkeeping.com/f...cteria-122748/
The article in PFK was a very good summary, written by one of the team of microbiologists (Dr. Josh Neufeld, if memory serves me correctly) who authored the above paper, from the University of Waterloo in Canada. I don't have the issue so may not be able to get much more on this, at present.