Growing in a temporary creek. Microscope images made with 10x,20x,40x & 60x objectives. Filaments of a uniform 7 µm width, a sheath appears to be present. It is possibly a species of Phormidium.
Stephen Skinner of the Herbarium of NSW says "330563 is a species of the large, and plastic, genus Phormidium, in the Phormidiaceae of the Oscillatoriales. In McGregor, GB (2007) Freshwater Cyanoprokaryota of North Eastern Australia 1 Oscillatoriales Flora of Australia Supplementary Series Number 24 ABRS/Canberra this appears close to P. papyraceum, but you would need the measurements."