Index Fungorum number: IF557145
Etymology: Name refers to its globose conidiomata.
Saprobic on dead needles of Abies alba. Sexual morph: undetermined. Asexual morph: Conidiomata 400–550 µm diam., 350–550 µm high, dark brown to black, pycnidial, solitary, immersed to erumpent, globose in section view, unilocular, convoluted, thick-walled, glabrous, ostiolate. Ostiole 150–200 × 100–220 µm, single, cylindrical, prominent, centrally located. Conidiomatal wall 10–60 µm wide, composed of brown to olivaceous, thick-walled cells of textura angularis to textura intricta in the outer and middle wall, becoming thicker, darker towards ostiolar region. Conidiophores arising from inner wall layer of locules, hyaline, cylindrical, verticillately branched at base and above, septate, smooth-walled. Conidiogenous cells 5–17 × 1–2 µm, hyaline, enteroblastic, phialidic, cylindrical to lageniform, integrated or discrete, determinate, formed as short or long lateral branches from the conidiophores immediately below septa, with minute collarette at the apex. Conidia 4–6.5 × 1–2 µm ( = 5 × 1.6 µm; n = 50), hyaline, allantoid, unicellular, smooth-walled, eguttulate.
Culture characters: Colonies on PDA, reaching 5 mm diam. after 2d at 25–30°C, white at first, becoming dark brown with age, cottony, flattened, dense, with entire to undulate margin, reverse pale brown.
Material examined: Italy, Province of Forlì-Cesena, Monte Fumaiolo, on dead aerial needles of Abies alba (Pinaceae), 2 July 2016, Erio Camporesi, IT3019 (MFLU 16-2054, holotype), ex-type living culture MFLUCC 16-1153 = KUMCC 16-0105; (KUM, HKAS 97500, isotype)
Notes: Collection MFLUCC 16-1153/IT3019 clustered with Cytospora sp. UCPH-DK-7 and formed a separated branch within Cytospora, with high support (Fig. 107). The morphology of conidiomata, conidiogenous cells and conidia in many Cytospora species are indistinguishable. Therefore, molecular data (LSU, ITS, rpb2) are used to delimit Cytospora species. Cytospora abietis (= Valsa abietis) and C. friesii (= V. friesii) were collected from Abies alba, but they separated from our collection by ITS sequence (other protein gene not available) (Adams et al. 2002, 2006). The sequence similarities between these two strains (CBS 185.42, CBS 194.42) and our collection MFLUCC 16-1153 are only 93% (511/551, 19 gaps) and 96% (528/551, 14 gaps) in ITS gene region. Therefore, our strain together with Cytospora sp. UCPH-DK-7 is introduced as a new species, Cytospora globosa.
Cytospora globosa (MFLU 16-2054, holotype). a Herbarium specimen. b–d Appearance of dark brown to black coniodiomata on the host. e, f Vertical sections of conidiomata. g Ostiole. h–j Sections of peridium. k–n Conidiophores, conidiogenous cells and developing conidia. o Conidia. p–q Germinating conidia. r–s Culture on PDA. Scale bars b = 1000 µm, c–d = 500 µm, e–f = 200 µm, g–j = 50 µm, k–q = 10 r–s = 20 mm.
Li WJ, McKenZie EHC, Liu JK, Bhat DJ, Dai DQ, Caporesi E, Tian Q, Maharachcikumbura SSN, Luo ZL, Shang QJ, Zhang JF, Tangthirasunun N, Karunarathna SC, Xu JC, Hyde KD (2020) Taxonomy and phylogeny of hyaline-spored coelomycetes. Fungal Diversity 100: pages279–801.