Hi Jon, I’ve added two new pictures (images 4 and 5), taken at the same place on 20 Nov. I thought this was just a slightly larger ant – it looked the same and it moved the same way. However, in the photos it looks more like a mutillid wasp than an ant. Some form of mimicry perhaps?
Yes Cath, 4 and 5 are a female mutillid wasp. It would be good to separate them as a different sighting, with a note as to their association with the Meranoplus.