Yes - it's a funny one. I have only 12 records of this species, and 8 of those records are from the Cotter Reserve stretch of the Cotter River where you found yours Christine. I've also found them just up the Paddys River from there, where Bullen Firetrail crosses. The other two locations are much further upstream and are the ones I've submitted records for. So in my experience to date, they are effectively restricted to the faster flowing stretches of the Cotter system where there are plenty of emergent or streamside rocks. And they are a late season species, being present only from very late January to early April. I've looked for them at a few locations along the Gudgenby River this season, without success.