Anthostomella obesa Daranagama, Camporesi & K.D. Hyde, in Daranagama, Camporesi, Tian, Liu, Chamyuang, Stadler & Hyde, Fungal Diversity 73: 217 (2015)

Indexfungorum number: IF 809518; Facesoffungi number: FoF 00319

Etymology: In reference to the much broader (stout) asci.

Saprobic on dead twigs and branches. Sexual morph: Ascomata immersed, solitary or rarely aggregated, appearing as blackened slightly raised, conical areas, in cross-section 200–280 × 250 µm high (x̄ = 265 × 250 µm, n = 10), globose to subglobose, ostiolar canal broad, surrounded by carbonaceous tissues, 75–90 µm diam. at base × 30 µm high (x̄ = 83 × 30 µm, n = 10). Peridium 25–30 µm diam. (x̄ = 28 µm, n = 10), with few cell layers, outwardly comprising dark brown cells of textura irregularis and inwardly comprising hyaline cells of textura irregularis with a central cell layer of light brown-yellow cells of textura angularis. Paraphyses 4.5 µm diam. (x̄ = 4.5 µm, n = 30), numerous, filamentous, septate. Asci 90–135 × 10–24 µm (x̄ = 125 × 18.4 µm, n = 30), 8-spored, unitunicate, cylindrical, short–pedicellate, apically rounded with a discoid, J+, apical apparatus, 2.5–3.5 × 0.5–1 µm (x̄ = 3.1 × 0.7 µm, n = 30). Ascospores: 13–18 × 6.7–9 µm (x̄ = 16 × 7.6 µm, n = 40), uniseriate, globose to equilateral ellipsoidal, unicellular, smooth-walled, germ slit, full length, straight. Asexual morph: undetermined.

Culture characteristics – Colonies on Difco OA at 25–27 oC reaching the edge of 4 cm Petri-dish in 4 weeks, at first whitish, felty, azonate, with diffuse margins, producing melanized black areas in the centre of the culture; reverse turning citrine (13).

Specimens examined – ITALY, Province of Forlì-Cesena, Passo delle Forche-Galeata, on Cornus sp. (Cornaceae), 2 January 2014, E. Camporesi IT1617 (MFLU 14-023, holotype), ex-type culture, MFLUCC 14-0171; ibid, 2 January 2014, E. Camporesi IT1617 (PDD, isotype).

Notes – Anthostomella obesa is reminiscent to A. kapitiae Whitton et al. (Lu and Hyde, 2000b). However, it differs in having a discoid, J+, apical apparatus, while in A. obesa, apical apparatus is faintly J+ and wedge-shaped. In addition, A. kapitiae has larger (17-23 × 10–12.5 µm) brown ascospores, in comparison to A. obesa, which has black, smaller spores (13–18 × 6.7–9 µm).

Fig 1. Anthostomella obesus (MFLU 14-023, holotype). a Habitat. b ascomata in wood. c Ascomata in side view. d Cross section of an ascoma. e ostiole. f. Paraphyses and peridium. g–i asci in water. j Asci in Meltzer’s reagent with J+ wedged shaped apical apparatus k, i ascospores in water. Scale bars: a = 1 mm, b, c = 200 µm, d = 100 µm, e, f = 30 µm, g–i= 10 µm.