Sclerococcum sphaerale
Anamorph: colonies sporodochial, 0.1-0.5 mm diam., circular and ± plane to punctiform or hemispherical, convex and wart-like, scattered on the surface of the host lichen, often occurring where isidia have been abraded, clearly delimited, dark brown to black. Stroma poorly developed or ± absent, setae and hyphopodia absent. Conidiophores poorly differentiated from vegetative cells, subglobose to ellipsoid or polyhedral, 4-6 (-8) µm diam., usually hyaline but sometimes becoming pale brown in parts. Conidiogenous cells 4-10 x 3-7 µm, subglobose, shortly cylindrical or ellipsoidal, sometimes rather inflated, hyaline to pale brown. Conidia arising in compact, rather irregular but frequently almost biseriate dry chains, (8-) 10-15 (-17) µm overall, irregularly subglobose to ellipsoidal, composed of 2-6 (-9) ± fused subglobose cells, walls moderately thick and ± smooth (sometimes becoming slightly uneven), brown to dark brown, almost black in mass, individual cells (4-) 6-10 µm diam.
Teleomorph: not known.
Assessed by Woods & Coppins (2012) as of Least Concern.
Parasitic on thalli of Lepra (Pertusaria) species, usually L. corallina. The sporodochia often develop from isidia, or the infection may suppress isidial production.
Common and widespread in upland Scotland and Wales, more scattered in other western regions. BLS map here.