Ascochyta neopisi W.J. Li, Camporesi & K.D. Hyde, sp. nov.
Etymology: Referring to its morphology similar to A. pisi, but phylogeny is distinct
Saprobic on dead stems of Colutea arborescens (Fabaceae). Sexual morph: undetermined. Asexual morph: Conidiomata 80–120 μm diam., 80–100 μm high, brown to black, pycnidial, solitary to gregarious or confluent, immersed, globose, unilocular, thick-walled, glabrous, with a dark brown papillate ostiole. Ostiole short, single, circular to oval, centrally located. Conidiomatal wall 10–20 μm wide, composed of thick-walled, brown cells, gradually merging with hyaline cells of textura angularis. Conidiophores reduced to conidiogenous cells. Conidiogenous cells 5–13 μm × 5–8.5 μm, hyaline, enteroblastic, phialidic, determinate, doliiform to ampulliform, smooth-walled, arising from the inner cavity of the conidiomata. Conidia 10–15 × 4–6.5 μm ( ̄x = 12 × 5 μm; n = 30), hyaline, ellipsoidal to ovoid, obtuse at both ends, straight or slightly curved, 1-septate, constricted at the septum, smooth, guttulate.
Culture characters: Colonies on PDA, reaching 15–20 mm diam. after 7 days at 25–30 °C, with white, flattened, dense, filamentous, aerial, fluffy hyphae on the surface, margin crenate, circular; reverse brown to yellowish in the middle zone, paler toward margins.
Material examined: Italy, Ravenna, Zattaglia, on dead stem of Colutea arborescens (Fabaceae), 30 January 2016, Erio Camporesi, IT2780 (MFLU 16-0291, holotype), living culture MFLUCC 16-1303, (KUM, HKAS 97465, isotype).
Notes: Ascochyta neopisi is similar to A. pisi in having pycnidial conidiomata and 1-septate conidia, but is distinguished by its conidiogenous cells. Ascochyta neopisi has phialidic conidiogenous cells, while A. pisi has annellidic conidiogenous cells. Phylogenetic analyses based on LSU, ITS, rpb2 and tub2 sequence data showed that A. neopisi formed a separate branch basal to A. fabae, A. pisi, A. syringae and A. viciae.
Ascochyta neopisi (MFLU 16-0291, holotype) a Herbarium package and specimen. b–c Appearance of brown conidiomata on the host. d Vertical section of conidiomata. e–f Section of peridium. g–j Conidiogenous cells and developing conidia. k Germinated conidium. l–m Conidia. n, o Culture on PDA. Scale bars b = 100 μm, c = 200 μm, d = 50 μm, e = 20 μm, f = 10 μm, g–j, l–m = 5 μm, k = 20 mm,n–o = 10 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.