Ascochyta rosae Tibpromma, Camporesi & K.D. Hyde, in Tibpromma et al., Fungal Diversity 83: 74 (2017)
Index Fungorum number: 552694; Facesofungi number: FoF 2774
Etymology: Named after the host family (Rosaceae).
Holotype: MFLU 14-0723
Saprobic on dead branch of Rubus ulmifolia Sexual morph: Ascomata 398–451 µm high × 364–398 µm diam. (x̄ = 446 × 380 µm, n = 5), immersed, solitary, or in small groups, uniloculate, globose, conspicuous at the surface, dull black, without hairs, long ostiolate. Peridium 16–29 µm wide, comprising 4–5 layers of reddish-brown cells of textura angularis. Hamathecium comprising 0.8–2.3 µm wide, dense, septate, unbranched, pseudoparaphyses. Asci 48–74 × 7–9 µm (x̄ = 58 × 8 µm, n = 25), 8-spored, bitunicate, fissitunicate, cylindrical, with short, club-shaped pedicel. Ascospores 13–17 × 3–5 µm (x̄ = 16 × 4.5 µm, n = 20), overlapping 1–2-seriate, fusiform, hyaline, 2-celled, 1-septate in the centre, deeply constricted at the septum, enlarged at the second cell, conical at the ends, with large guttules and with appendages at the ends. Asexual morph: Produced on sterilized bamboo pieces with pine needles on water agar. Coelomycetous. Conidiomata 68–105 × 77–98 µm, pycnidial, yellow orange to black, globose, covered by dense vegetative hyphae, uniloculate, solitary to scattered. Conidiophores reduced to conidiogenous cells. Conidiogenous cells 5.3–8.6 9 3.2–5.1 µm (x̄ = 6.6 × 3.9 µm, n = 20), holoblastic, annelidic, globose to oblong, hyaline, and formed from the inner layer of pycnidium wall. Conidia 3.2–4.4 × 1.2–1.8 µm (x̄ = 3.7 × 1.5 µm, n = 40), cylindrical, rounded at both ends, sometimes slightly curved, aseptate, hyaline, guttulate.
Material examined: ITALY, Galeata Province, near Strada San Zeno, on dead branch of Rubus ulmifolia (Rosaceae), 19 June 2014, Erio Camporesi, IT1946 (MFLU 14-0723, holotype); ex-type living culture MFLUCC 15-0063. (HKAS 94596bis, paratype).
GenBank Numbers: LSU: KY496731, ITS: KY496751, SSU: KY501119, RPB2: KY514409
Note: Ascochyta rosae is introduced with both sexual and asexual morphs (Tibpromma et al. 2017).