Phyllosticta pachysandricola
Phyllosticta pachysandricola Wikee, Motohashi & Crous,
Index Fungorum: IF805658; Facesoffungi: FoFxxxxx; MycoBank: MB805658.
Pathogenic on Pachysandra terminalis leaves. Leaf spots circular to ellipsoid, pale brown to brown, often extend with concentric rings, 6–16 mm diam., surrounded by a dark brown border. Sexual morph: Unknown. Asexual morph: Conidiomata (on PNA) 90–140 × 25–80 μm diam., pycnidial, amphiphyllous, sparse, solitary or aggregated, immersed at first, then erumpent breaking through the epidermis, brown to dark brown, subglobular. Peridium composed of depressed or irregular cells with 1–4 layers, brown to dark brown, hyaline or paler toward the inside. Ostiole central. Conidiogenous cells 5–12 × 2–2.5 μm, integrated, lining the innermost layer of the pycnidial wall, cylindrical, straight or slightly curved, hyaline, proliferating percurrently at least once, with minute periclinal thickenings. Conidia 5.5–8.5 × 4.5–7.5 μm, sporulating holoblastically, solitary, unicellular, spherical, ellipsoid to obovoid, truncate at the base or rounded at both ends, containing numerous greenish guttulae, surrounded by a mucous sheath, rarely with a short apical appendage.
Culture characteristics: Colonies reaching 36−44 mm diam. on PDA after 4 d in the dark at 25 °C.
Representative isolates: Japan, Hokkaido, Asahikawa, on Pachysandra terminalis, K. Motohashi, C. Nakashima & T. Akashi, 7 June 2006, holotype TFM : FPH7877, isotype MUMH 10488, MUCC 124 = NBRC 102276 (ex-type culture).
Host: Pachysandra terminalis (Wikee et al. 2013).
Known distribution: Japan (Wikee et al. 2013).
GenBank Numbers: ITS - AB454317, LSU - AB454317, ACT - AB704232.
Notes: Another species has been recorded from Pachysandra, P. pachysandrae, which van der Aa & Vanev (2002) excluded from Phyllosticta s. str. based on its conidia (unicellular, oblong, 4.5–6 × 1 μm) that indicate placement in Asteromella. The Japanese collection on Pachysandra is thus described as a new species, P. pachysandricola, in accordance to the morphological differences noted by Motohashi et al. (2009).
References:
Aa HA van der, Vanev S (2002) A revision of the species described in Phyllosticta. Centraalbureau voor Schimmelcultures, Utrecht, The Netherlands.
Motohashi K, Inaba S, Anzai K, Takamatsu S, Nakashima C (2009) Phylogenetic analyses of Japanese species of Phyllosticta sensu stricto. Mycoscience 50: 291–302.
Wikee S, Lombard L, Nakashima C, Motohashi K, Chukeatirote E, Cheewangkoon R, McKenzie EHC, Hyde KD, Crous PW (2013) A phylogenetic re-evaluation of Phyllosticta (Botryosphaeriales). Studies in Mycology 76: 1–29.