Scorias Fr., Syst. mycol. 3(2): 269, 290 (1832)
Facesoffungi number: FoF 07589
Dothideomycetes, Dothideomycetidae, Capnodiales, Capnodiaceae
Epiphytic or saprobic on sugary exudates from insects on the surface of branches or living leaves. Thallus composed of dark brown to brown, cylindrical, branched, septate and constricted at septum, dense mycelium. Sexual morph: see Chomnunti et al. (2011). Asexual morph: Conidiomata dark brown at the base, becoming paler towards apex, pycnidial, gregarious, superficial, flask-shaped, tapering to the apex, branched at the base. Pycnidial wall composed of dark brown, thick-walled cells of helical twisting at the lower half part, becoming pale brown, thin-walled cells of textura porrecta at the upper part. Conidiophores formed from inner layers of pycnidial wall. Conidiogenous cells not observed. Conidia hyaline, ellipsoid, unicellular, smooth-walled, eguttulate.
Type species: Scorias spongiosa (Schwein.) Fr., Syst. mycol. (Lundae) 3(2): 291 (1832)
Notes: Capnodium, Conidiocarpus, Leptoxyphium, and Scorias are sooty moulds with hyaline, ellipsoid conidia (Chomnunti et al. 2011, this study). Leptoxyphium has grey-brown, superficial, synnematous conidiomata whereas they are pycnidial conidiomata in Capnodium, Conidiocarpus and Scorias. Conidiocarpus has superficial pycnidia differentiated into a basal stalk and a globose locule at the upper half, while Capnodium and Scorias have superficial, flask-shaped pycnidia tapering to the apex (Chomnunti et al. 2011). Scorias was separated from Capnodium by its sexual morph. Capnodium has 8–10-spored, bitunicate, clavate, ovoid or saccate, aparaphysate, apedicellate asci and brown, oblong or ovoid and some reniform, 3–5 trans-septate ascospores with a verrucose wall. Scorias has 8-spored, bitunicate, oblong to saccate, apedicellate asci with a long ocular chamber and brown, fusiform, 3–4 trans-septate ascospores with the upper cells slightly wider than the lower cells (Chomnunti et al. 2011).
Chomnunti et al. (2011) epitypified Scorias spongiosa based on a collection on a living leaf of Entada sp. (Fabaceae) in Thailand, and confirmed its placement in Capnodiaceae. Hongsanan et al. (2015) added S. mangiferae Hongsanan et al. from a branch of Mangifera sp. (Anacardiaceae) in Thailand. An additional eleven species are listed in Index Fungorum (2019), but they have not been studied with molecular data.
Distribution: Thailand, South Africa, USA (Chomnunti et al. 2011, Crous et al. 2011b, this study).
Scorias spongiosa (asexual morph) a Host plant. b, c Sooty moulds on the surface of host plant. d–j Immature ascomata and pycnidia. k Ostiole surrounded by hyaline hyphae. l Abundant conidia at base of pycnidium and pycnidia wall. m, n Conidia. Scale bars d =100 μm, e, j = 40 μm, f–i = 20 μm, k–l =10 μm, n, m = 5 μm.