Immersidiscosia eucalypti
Immersidiscosia eucalypti (Pat.) Kaz. Tanaka, Okane & Hosoya, in Tanaka, Endo, Hirayama, Okane, Hosoya & Sato, Persoonia 26: 94 (2011)
Index Fungorum number: IF 519747; Facesofungi number: FoF 03385
Basionym: Cryptostictis eucalypti Pat., Cat. Pl. Cell. Tunisie: 123. 1897
: Discosia eucalypti (Pat.) Nag Raj, Coelomycetous Anamorphs with Appendage-bearing Conidia: 308. (1993)
Holotype: MFLU 16-1372
Saprobic on dead leaves of Quercus pubescens. Sexual morph: Unknown. Asexual morph: coelomycetous. Conidiomata 290–330 μm (x̄ = 316 μm) diameter, 100–130 μm (x̄ = 116 μm) high, conspicuous, pycnidial, subglobose to sometimes lenticular in section view, semi-immersed, scattered or aggregated and confluent, with relatively thin stromatic base, black, glabrous, epidermal, unilocular or multilocular and rounded. Peridium 18–21 μm wide, composed of 3–4 layers, with outer 2–3 layers light brown and inner layer hyaline, composed of thin-walled cells of textura angularis. Conidiogenous cells 8–10 × 1–3 μm (x̄ = 9 × 2 lm, n = 20), subcylindrical, developing directly on the inner-most layer of peridium-wall, phialidic, each producing a single conidium, integrated, hyaline, smooth-walled. Conidia 15–20 × 2–4 μm (x̄ = 17 × 3 μm, n = 40), cylindrical to subcylindrical, slightly curved, 3-septate, slightly constricted at the septa, hyaline, with cells of unequal width, basal cell obconic, 2 median cells subcylindrical, second cell adjacent to the base 5–6 lm (x̄ = 5.5 μm) long, third cell adjacent to apex 6–7 lm (x̄ = 6.5 μm) long, apical cell conical with a rounded apex; apical and basal cells with an unbranched, filiform, flexuous or straight appendage; apical appendage 8–14 μm (x̄ = 12 μm); basal appendage 8–15 μm (x̄ = 12.5 μm).
Culture characteristics: Colonies on PDA moderately growing, reaching 25–30 mm diameter after 8 days at 20–25 °C, sporulation after 3 weeks, medium sparse, circular, flat, slightly rough at surface with entire edge, with a well-defined margin, waxy with sparse mycelium; from above: brown at the centre, yellowish to light brown at the margin; from below, dark brown at the centre, yellowish to light brown at the margin; mycelium light brown to yellowish with tufting; not producing pigments in PDA medium.
Material examined: ITALY, Province of Forlı`-Cesena [FC], Fiumana di Predappio, on dead land leaves of Quercus pubescens L. (Fagaceae), 9 February 2016, E. Camporesi, IT 899 (MFLU 16-1372), living cultures KUMCC 16-0181.
GenBank: ITS: MF173609, LSU: MF173608.
Notes: Host specificity of the taxa in this genus has not yet been clarified according to Immersidiscosia eucalypti has been recorded from various plant families (Fagaceae, Lauraceae, Myrtaceae, Primulaceae). The members of the Immersidiscosia seem to be cosmopolitan in distribution since they have been recorded from both temperate and tropical countries (France, Italy, Japan, Tunisia) (Tanaka et al. 2011). Further collections are essentially required to expand the Immersidiscosia genus.
Figure x. Immersidiscosia eucalypti. a Specimen with conidiomata. b Close up of conidiomata. c Section of conidioma. d Section of peridium. e Conidiogenous cells. f–h Conidia. i Germinated conidium. j Colony from above. k Colony from below. Scale bars c = 50 μm, c = 20 μm, d = 20 μm, e–I = 10 μm.
References:
Hyde KD, Norphanphoun C, Abreu VP, Bazzicalupo A, et al. 2017 – Fungal diversity notes 603–708: taxonomic and phylogenetic notes on genera and species. Fungal Diversity 87, 1–235.
Last update: 30 November 2021