Any chance you know what the Acacia is? The reason I ask is because Endoraecium also forms galls on the stems of Acacia dealbata (see A.R. McTaggart, C. Doungsa-ard, A.D.W. Geering, M.C. Aime, R.G. Shivas (2015) A co-evolutionary relationship exists between Endoraecium (Pucciniales) and its Acacia hosts in Australia. Persoonia 35: 50–62.) Easy to separate Uromycladium from Endoraecium under a compound microscope - 40x objective is adequate.