Fissuroma neoaggregata Phookamsak & K.D. Hyde, sp. nov.
Index Fungorum number: IF551630
Etymology: The epithet Bneoaggregata^ refers to its similarity with Fissuroma aggregata
Holotype: MFLU 11-0146
Saprobic on bamboo. Sexual morph: Ascostromata 290–410μm high, 870–1100μm diam., dark brown, scattered, solitary to gregarious, immersed in host epidermis, visible as numerous, raised, dome-shaped areas on the host surface, hemisphaerical to depressed conical, with flattened base, wedge-shaped at the rim, uni-loculate, glabrous, walls slightly rough, coriaceous, ostiolate. Ostioles central, apapillate with short carbonaceous, and thin, slit-like opening. Peridium 45–70μm wide, of unequal thickness, poorly developed at the base, composed of several layers, of small, dark brown to black, pseudoparenchymatous cells with host cells plus fungal tissue, arranged in a textura angularis to textura prismatica, with palisade-like cells at rim. Hamathecium composed of dense, 0.5–1μm wide, filiform, trabeculate pseudoparaphyses, anastomosing among the asci, embedded in a hyaline gelatinous matrix. Asci (155–)160–190(–197)×15–17(–18) μm (x =177×16.5μm, n=20), 8-spored, bitunicate, cylindrical to obclavate, with furcate to truncate pedicel, apically rounded, with an indistinct ocular chamber. Ascospores (39–)(41–)47–50(–54)×7–9μm (x =47.7×8.7μm, n=25), overlapping uni- to bi-seriate, hyaline, broadly fusiform, with acute ends, 1-septate, slightly constricted at the septum, smooth-walled, guttulate, surrounded by a thin sheath. Asexual morph: Undetermined.
Culture characteristics: Colonies on MEA reaching 45–46 mm diam. after 4 weeks at 25–30 °C, colonies circular, medium dense to dense, flattened, slightly raised with low concave edge, dull, slightly rough with edge entire, velvety to woolly, smooth aspect, slightly radiating outwardly; from above, white to greyish-brown at the margin, dark grey to blacknish at the centre, with small, black droplets; from below: light brown to brown at the margin, dark grey to blackish in the middle, white brown to light brown at the center, radiating with reddish-brown concentric rings, the centre seperating from the middle part; not producing pigmentation in agar.
Material examined: THAILAND, Chiang Rai Province, Muang District, Huai Mae Sai Waterfall, on dead stem of bamboo (Poaceae), 10 March 2010, R. Phookamsak, RP0025 (MFLU 11-0146, holotype), living culture, MFLUCC10-0554, BCC; ibid., Khun KornWaterfall, on dead stem of bamboo, 24 November 2012, R. Phookamsak, RP0122 (MFLU 12-2468), living culture, MFLUCC 13-0227, BCC.
Notes: Liu et al. (2011) represented F. aggregata by a collection MFLU 11-0146; living culture, MFLUCC10-0554. However, Liu et al. (2011) did not examine the type of F. aggregata (≡ Melanopsamma aggregata), but used morphological characters to name the species. In Liu et al. (2011) , the phylogenetic analyses showed that F. neoaggregata clusters with F. aggregata (KT 984 and KT 767) in Aigialaceae and was separated from the type species, F. maculans. Thus, Liu et al. (2011) identified the F. neoaggregata as F. aggregata. In this study, the type of F. aggregata (≡ Melanopsamma aggregata) is examined and shows that the type of F. aggregata differs from F. neoaggregata by having ascostromata with long carbonaceous, thick, opaque, rimlike openings and larger of ascospore size. Whereas, F. neoaggregata has ascostromata with thin, short, slightly shiny, slit-like openings and smaller ascospores. Therefore, we introduce the species with a new name, F. neoaggregata due to the morphological characters, phylogenetic analyses and TEF1 gene pairwise comparison. A description and illustration are provided in this study.
Fig. 1 Fissuroma neoaggregata (MFLU11-0146, holotype). a Appearance of ascostromata on host surface. b Section through ascostroma. c, d Section through peridium. e Pseudoparaphyses stained in cotton blue. f, g Asci. h Asci stained in Indian ink. i–k Ascospores. l Ascospore stained in Indian ink.m, n Cultures on MEA (m=from above, n=from below). Scale bars: b=200μm, e–h=50μm, c=20μm, d, i–l=10μm