Pleosporales » Melanommataceae » Petrakia

Petrakia echinata

Petrakia echinata (Peglion) Syd. & P. Syd. (1913).

Epicoccum echinatum Peglion, Malpighia 8: 459 (1895).

            Index Fungorum number: IF 192652; Facesoffungi number: FoFxxx, Fig. 1

Description:

Parasitic on living leaves. Synasexual morph: Conidiomata 105–110 μm diam., 105–115 μm high, sporodochial, superficial, scattered or in groups, dark brown to black.  Conidiophores reduced to conidiogenous cells.  Conidiogenous cells holoblastic, hyaline, smooth. Macroconidia and mycopappus-like propagules scattered or in groups, on dark brown, somewhat circular necroses on the upper surface of living leaves.  Mycopappus-like propagules shortly stalked, sub-globose to ellipsoid, multicellular, parenchymatous, comprising somewhat isodiametric, globose cells, hyaline to pale brown, with up to 6 filamentous, hyaline hyphal appendages. Macroconidia 20−30 × 18−25 µm (x̄ = 26.2 × 21.1 µm, n = 10), formed on epiphyllous sporodochia, embedded in the leaf tissues with a cone shaped stroma, mature sporodochia blackish brown. Macroconidia formed on epiphyllous sporodochia, embedded in the leaf tissues in circular shaped stroma, mature sporodochia blackish brown. Macroconidia dark brown, muriform, ellipsoid to elongated spindle-shaped, cells angular, somewhat cubic, cell walls dark-brown, smooth. Macroconidia bearing one apical and 0–4 (6) side projections, projections straight with conical to spherical tips, hyaline to light brown, mostly without septa; pedicels up to 11–30 µm long and 3.5–7.8 µm wide. Sexual morph: Undetermined.

Material examined: France, from leaf of Acer pseudoplatanus (Sapindaceae), Van der Aa H.A. (BR5020172196214).