Microbotryum dumosum (Vánky & Oberw.) Vánky


Ustilago dumosa Vánky & Oberw.


Sori in slightly swollen stems and branches, filled with a purplish brown semi-agglutinated spore mass.

Spores globose, ovoid, ellipsoidal or slightly irregular, 11–15 × 9.5–12.0 µm, violet-tinted yellowish brown; wall in LM reticulate, punctate-reticulate or punctate in a reticulate pattern, 6–9 meshes per spore diameter; muri 0.5–0.8 µm high, in median view appearing as blunt projections, in SEM reticulate, with tubercles in the interspaces and on muri.

Host family: Polygonaceae
Host species: Rumex dumosus Meisn.
Rumex pulcher L.
Rumex tenax Rech.f.


States & Territories: NSW, TAS