Premilcurensis senecionis Tibpromma, Camporesi & K.D. Hyde, 2015

Tibpromma, Saowaluck, Promputtha, Itthayakorn, Phookamsak, Rungtiwa, Boonmee, Saranyaphat, Camporesi, Erio, Yang, Jun-Bo, Bhakali, Ali H., Mckenzie, Eric H. C. & Hyde, Kevin D., 2015, Phylogeny and morphology of Premilcurensis gen. nov. (Pleosporales) from stems of Senecio in Italy, Phytotaxa 236 (1), pp. 40-52 : 45

Premilcurensis senecionis Tibpromma, Camporesi & K.D. Hyde , sp. nov. Fig. 2

Index Fungorum number: IF551294, Facesoffungi number: FoF: 00700

Etymology: refers to the host genus from which the fungus was isolated.

Holotype: MFLU 14-0678

Saprobic on decaying stem of Senecio sp. ( Asteraceae ). Sexual morph: Ascostromata 160–215 μm high, 230–265 μm diam. (x = 195 × 242 μm, n = 5), superficial, semi-immersed at the base, globose to subglobose, solitary or in small groups, glabrous, dark brown to black, scattered on the host surface, base not easily removed from the substrate, ostiole central, papilla minute, thin-walled, shiny, like charcoal. Peridium 20–28 μm wide, thick, externally multi-layered,

heavily pigmented at the surface, composed of thick-walled light brown cells of textura angularis , inwardly cells thinwalled. Hamathecium comprising numerous, 1.1–1.5 μm wide, filiform, cellular, branched, hyaline pseudoparaphyses. Asci 58–65 × 7–10 μm (x = 60 × 10 μm, n = 30), 8-spored, bitunicate, fissitunicate, cylindrical to cylindric-clavate, short pedicellate, rounded at the apex, with well-developed ocular chamber. Ascospores 18–27 × 4–5 μm (x = 22 ×

4 μm, n = 50), overlapping uni- to bi-seriate, initially hyaline, becoming yellow-green to yellow-brown at maturity,

fusiform-cylindrical to elongate fusiform, with rounded ends, usually 3–5-septate, straight to slightly curved, constricted at the central septum, with wing-like appendages, smooth-walled, with small guttules in each cell. Asexual morph:

Undetermined.

Culture characteristics: on PDA reaching 2 cm diam. after 2 weeks at 16°C, later with dense mycelium, with circular, rough margin, flattened; upper surface white at first, pale yellow after 4 weeks; reverse cinnamon; hyphae septate, branched, hyaline, thin-walled.

Material examined: ITALY, Province of Forlì-Cesena [FC], Premilcuore, on dead stems of Senecio sp. , 26 May

2013, Erio Camporesi, IT 1310 ( MFLU 14-0678 , holotype) ; ex-type living culture, MFLUCC 13-0575 . ( MFLU 15 -

0186, HKAS 88739 , isotypes ); Ibid. ( MFLU15-0752 bis, MFLU 15-0753 tris, MFLU 15-0754 tetrakis, MFLU 15 -

0755pentakis, MFLU 15-0756hexakis, MFLU 15-0757heptakis, MFLU 15-0758enneakis, paratypes).

Notes: Barr (1979) introduced the family Phaeosphaeriaceae typified by Phaeosphaeria with P. oryzae (Miyake

1909) as the type species. Fifteen genera were included in this family, although Kirk et al. (2008) later accepted 35

genera. Its characteristics are similar to taxa in the family Leptosphaeriaceae and the two are often confused ( Hyde et al. 2013, Phookamsak et al. 2014, Ariyawansa et al. 2015). The taxa within Phaeosphaeriaceae are often associated with monocotyledons, have a peridium of pseudoparenchymatous cells and asexual morph of pycnidial coelomycetes,

mostly identified as phoma-like or stagonospora-like ( Hyde et al. 2013). Premilcurensis is similar to some species of Nodulosphaeria and Leptosphaeria ( Table 2), but based on phylogeny Nodulosphaeria and Leptosphaeria are not congeneric with our taxon ( Fig. 1 ).

Figures

FIGURE 1. Phylogenetic tree obtained from RAxML analysis based on combined LSU, ITS and SSU sequence data. Bootstrap support values for maximum parsimony (MP, left), maximum likelihood (ML, middle) higher than 60% and Bayesian posterior probabilities (BYPP, right) greater than 0.95 are provided at the nodes. The tree is rooted with Halojulella avicenniae (BCC 20173). Newly generated sequences and ex-types strains are in bold.

FIGURE 2. Premilcurensis senecionis (MFLU 14-0678, holotype). a, b, c Ascostromata on host substrate. d Section of ascoma. e Section through peridium. f Relatively wide cellular pseudoparaphyses. g–i Asci. j Ocular chamber of ascus. k–m Ascospores with winglike equatorial appendage. Scale bars: a = 200 μm, b–d = 100 μm, e, g, h, i = 20 μm, f = 1 μm, j = 5 μm, k–m = 10 μm.