Doassansiopsis hydrophila (A. Dietr.) Lavrov

Synonyms

Doassansia (Doassansiopsis) domingensis Cif.
Doassansia hydrophila (A. Dietr.) B. Lindeb.
Doassansia martianoffiana (Thüm.) J. Schröt.
Doassansiopsis martianoffiana (Thüm.) Dietel
Protomyces martianoffianus Thüm.
Sphaeria hydrophila A. Dietr.

Description

Sori in leaves, initially as small pale yellow circular spots, later brown or reddish brown areas, sometimes covering most of the leaf surface. Spore balls appearing within the spots, usually on the abaxial side of the leaf, as very minute brown scattered or gregarious pycnidium-like bodies, liberated when the epidermis disintegrates.

Spore balls globose, subglobose or ovoid, 120–250 µm long, composed of a central mass of sterile parenchymatous cells surrounded by a layer of spores and a thin cortex of sterile cells.

Spores usually in 1 layer, sometimes partially in 2 layers, closely packed, radially elongate, irregularly prismatic, polyhedral or subpolyhedral, 9.5–22.0 × 6.5–12.0 µm, light yellowish brown, with a smooth c. 0.5 µm thick wall and finely granular contents.

Central sterile cells varying in shape and size, irregularly polyhedral, (4–) 7–16 (–24) µm diam., empty, with smooth subhyaline to pale yellow c. 0.5 µm thick wall.

Cortical cells small, mostly tangentially flattened, irregularly polyhedral, 4–8 µm long, lacking granular contents, with a light brown smooth wall c. 0.5 µm thick.

Anamorph: Savulescuella aquatilis (Peck) Cif.

Hosts
   
Host family: Potamogetonaceae
   
Host species: Potamogeton tricarinatus A.Benn. & F.Muell.

Distribution

States & Territories: NSW