Didymella cirsii Mapook, Camporesi& K.D. Hyde.
Index Fungorum number: IF550935, Facesoffungi number: FoF00441; Fig. 2
Etymology: Name reflects the host genus Cirsium, from which this species was isolated.
Holotype: MFLU 14–0023

Saprobic on a dead stem of Cirsium sp., noticeable as black dots on host surface. Sexual morph Ascomata (118–)165–209(–243)×(121–)200–245μm (x=193×209μm, n=10), immersed or erumpent, solitary or scattered, globose to subglobose, brown to dark brown, without subiculum covering host, Ostiole central. Peridium (15–)30–34μm wide, thick, dark brown, comprising dark brown cells of textura angularis. Hamathecium comprising 1–1.5μm wide, cylindrical to filiform, pseudoparaphyses. Asci (60–)67–88(–109)×13–16μm (x=85×15μm, n=10), 8-spored, bitunicate, fissitunicate, cylindric-clavate, slightly curved, smoothwalled, apically rounded, short pedicellate, with an ocular chamber (ca. 4–6μm wide). Ascospores 20–26×6–7μm (x=23×7μm, n=20), 1–2-seriate, overlapping in the ascus, ellipsoid to obovoid, hyaline, 1-septate, constricted at septa,widest at the centre and tapering toward narrow ends, straight or slightly curved, thick and smooth-walled. Asexual morph Undetermined.

Culture characters: Ascospores germinating on MEA within 24 hr and germ tubes produced from both ends. Colonies growing onMEA, reaching 20mmdiam. after 5 days at 16–18 °C, flat, margin crenate, white to olivaceous grey, fine mycelium, medium dense to dense, septate, hyaline.

Material examined: ITALY, province of Forlì-Cesena [FC], Fiumicello – Premilcuore, on dead stems of Cirsium sp., 5 May 2013, E. Camporesi IT1218 (MFLU 14–0023, holotype), ex-type living culture, MFLUCC 13–0687. GenBank LSU: KP744483; SSU: KP753951.

Notes: Didymella cirsii resembles species of Didymella (Didymellaceae) based on its immersed, erumpent ascomata with one-celled ascospores. It differs from Didymella applanata in the size of ascomata, asci and ascospores. Phylogenetic analysis of combined ITS and LSU genes indicated that Didymella cirsii belongs in Didymellaceae with high bootstrap support (Fig. 1), but as a distinct lineage; thus a new species is proposed.

Fig. 1 Phylogram generated from Maximum likelihood (RAxML) analysis based on combined LSU and ITS sequence data of Didymellaceae. Maximum likelihood bootstrap support values greater than 50 % are indicated above or below the nodes, and branches with Bayesian posterior probabilities greater than 0.95 are given in bold. The ex-types (reference strains) are in bold; the new isolates are in blue. The tree is rooted with Ascochytahordei var. Hordei CBS 544.74

Fig. 2 Didymella cirsii (holotype) a Ascomata b Section through of ascoma c Ostiole d Peridium e Pseudoparaphyses f-h Immature andmature asci i-l Ascospores M Germinating ascospores. Scale bars: a=200μm, b, f-h=50μm, c-e=20μm, i-l, m=10μm.