Restiosporium flexuosum Vánky


Sori in all nuts of an inflorescence, ovoid, flattened, with an acute tip, visible between the spreading floral envelopes, 1.5–2.5 mm long, 0.5–1.0 mm wide, filled with a dark brown powdery mass of ephemeral spore balls and spores. The fungus induces transvestism in the host.

Spores solitary when mature, globose, ovoid, ellipsoidal, elongate or subpolyhedrally irregular, rarely with short acute tips at the angles and narrow lines on the surface, 9–16 × 7–12 µm, pale olivaceous brown; wall ±uniformly 0.5–1.5 µm thick; in LM smooth, in SEM all spores finely and densely verruculose.

Host family: Restionaceae
Host species: Desmocladus flexuosus (R.Br.) B.G.Briggs & L.A.S.Johnson


States & Territories: WA


Two smut fungi, R. flexuosum and R. desmocladi, occur on Desmocladus flexuosus. Restiosporium flexuosum differs from R. desmocladi (type on Desmocladus elongatus) by the ephemeral spores balls, more rounded spores and thinner, finely and densely verruculose spore walls.