Sub-social Crab Spider

Size about 5mm. Fast spider found in bushland with mixed habitats. It seemed quite unique and seemed interested in what I was doing. It ran away visiting various leaves. This species seems to vary a bit. The one individual I found and believe to be this species had a black thorax, bright brown abdomen, undulated from the back and side, pattern on top, a bit bigger than the thorax, flattened round. Two front legs long and dark. Third leg row short, last legs a bit longer. Both bright creamy colour. Interesting that it seems to be a social spider, because I had the feeling that it was quite clever and agile. See https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4137311/