Amphisphaeria acericola Senan., Camporesi & K.D. Hyde, 2019

Senanayake, Indunil C., Lian, Tong-Tong, Mai, Xiao-Min, Camporesi, Erio, Zeng, Yu-Jia, Tian, Sheng-Li & Xie, Ning, 2019, Taxonomy and phylogeny of Amphisphaeria acericola sp. nov. from Italy, Phytotaxa 403 (4), pp. 285-292 : 289-290

Amphisphaeria acericola Senan., Camporesi & K.D. Hyde , sp. nov. FIGURE 2

Index Fungorum number: IF553774, Facesoffungi number: FoF03594

Etymology: — Named after the host genus on which the fungus occurs.

Holotypus: — MFLU 16–2479

Saprobic on branches of Acer campestre L. Sexual morph Ascomata 275–300 μm high, 350–450 μm diam. (x = 280 × 407 μm, n = 10), immersed, visible as black spots, solitary, scattered, subglobose, short, wide papillate, ostiole periphysate, dark brown. Peridium 28–40 μm (x = 35 μm, n = 15), comprising inner layer of hyaline cells of textura angularis, outer layer of brown cells of textura angularis. Paraphyses 2–5 μm wide (x = 3 μm, n = 10), few, longer than asci, cellular, septate, embedded in gelatinous matrix. Asci 100–130 × 8.5–11 μm (x = 113 × 9.6 μm, n = 20), 8-spored, unitunicate, cylindrical, short, bilobed pedicellate, apically rounded, with a J+, apical ring. Ascospores 16–24 × 6–8 μm (x = 19 × 6.5 μm, n = 20), overlapping uniseriate, ellipsoidal to oval, hyaline when young, pale brown at maturity, unicellular to median, thin, uniseptate, not constricted at the septum, smooth-walled. Asexual morph Undetermined.

Culture characteristics: — Colonies on PDA reaching 2 cm diam., after 10 days at 18 ºC, moderately fast growing, white, circular, flat, slightly wooly, smooth margin.

Material examined: — ITALY, Province of Forlì-Cesena, Galeata, Strada San Zeno, on branch of Acer campestre L ( Sapindaceae ), 26 Mar 2014, E. Camporesi, IT 1779, ( MFLU 16–2479 holotype), ex-type living cultures, MFLUCC 14–0842.

Notes: — Samarakoon et al. (2018) has provided a key for the accepted Amphisphaeria species. According to the phylogenetic analyses in this study, Amphisphaeria acericola is clearly distinct from other five species which molecular data presence. Amphisphaeria acericola is morphologically somewhat similar to A. millepunctata , A. pakistanae and A. pseudoumbrina .

However A. pakistanae has large, globose ascomata, narrow papilla, pale brown to olivaceous ascospores arranged uniseriately while A. acericola comprises small, subglobose ascomata, wide papilla, brown ascospores arranged overlapping uniseriately. Amphisphaeria millepunctata comprises ascomatal wall with cells of textura intricata and asci with uniseriately arranged ascospores while A. acericola has compressed cells of textura angularis in the peridium and ascospores arranged in overlapping uniseriately. Both Amphisphaeria acericola and A. pseudoumbrina have similar characters such as immersed, oblate ascomata, J +, discoid, cylindrical asci with rugose-walled, brown, 1-septate, non constricted ascospores. However there is a significant difference between some characters as shown below ( Table 2).

Figures

FIGURE 2. Amphisphaeria acericola (MFLU 16–2479). a. Ascomata on substrate. b. Cross section of ascomata. c. Peridium. d–f.Asci. g. J+ apical ring. h–k. Ascospores. Scale bars: a = 200 μm, b = 100 μm, c, g, h–k = 10 μm, d–f = 20 μm.