Neohelicascus elaterascus
Neohelicascus elaterascus (Shearer) W. Dong, K.D. Hyde & H. Zhang
Index Fungorum number: IF557925; Facesoffungi number: FoF09267
Basionym: Kirschsteiniothelia elaterascus Shearer, Mycologia 85:963 (1993).
Synonymy: Morosphaeria elaterascus (Shearer) S. Boonmee & K.D. Hyde, Mycologia 103: 705 (2012), Helicascus elaterascus (Shearer) H. Zhang & K.D. Hyde, Sydowia 65: 158 (2013)
Saprobic on decaying wood submerged in freshwater. Sexual morph: Pseudostromata 205–250 μm high, 170–200 μm diam., clustered, immersed, unilocular, mammiform, coriaceous, with ostiolate papilla, visible on the host surface as blackened ostiolar dots. Peridium 20–30 μm thick, comprising several layers of brown, thin-walled, pseudoparenchymatous cells, outer layer partially occluded with the host cells, deeply pigmented, inwardly hyaline, forming a textura angularis in the upper regions and a textura prismatica at sides and angles of base. Pseudoparaphyses 1–3 μm diam., abundant, cellular, cylindrical, hyaline, sparsely septate. Asci 95–130 × 17–24 μm (x̄ = 112 × 21 μm, n = 15), 8-spored, bitunicate, fissitunicate, clavate, endoascus separating from ectoascus at time of ectoascus dehiscence, base of endoascus long, narrow and coiled within ectoascus, up to 210 μm long. Ascospores 23–28 × 8–11 μm (x̄ = 25 × 9 μm, n = 25), overlapping uni- or bi-seriate, sometimes overlapping tri-seriate, ellipsoidal, brown, 1-septate, constricted at septum, asymmetrical, apical cell slightly longer than basal cell, curved, thin-walled, smooth in optical microscope, surrounded by a gelatinous sheath. Asexual morph: Undetermined. (Dong et al. 2020)
Culture characteristics: On PDA, colony circular, reaching 40 mm in 45 days at 25 °C, dark brown to black from above, black from below, surface rough, dry, raised, edge undulate.
Material examined: THAILAND, Phayao Province, on submerged wood in a stream, 23 February 2018, X.D. Yu, Y19 (MFLU 18-0997), living culture MFLUCC 18-0985; Chiang Mai Province, Mushroom Research Center, on submerged wood in a stream, 2 April 2018, X.D. Yu, Y29 (MFLU 18-1007), living culture MFLUCC 18-0993.
Notes: Our new collections MFLUCC 18-0985 and MFLUCC 18-0993 are identified as Neohelicascus elaterascus based on morphological and molecular evidence. Shearer (1993b) described verrucose ascospores from the holotype (C-76-1), while our collections have smooth ascospores which are also described by Hyde et al. (2020a). Neohelicascus elaterascus is commonly reported on submerged wood from many countries as listed above. (Notes from Dong et al. 2020)
Freshwater distribution: Brunei (Ho et al. 2001), Chile (Shearer 1993), China (Tsui et al. 2000; Luo et al. 2004), Japan (Tanaka et al. 2015), Peru (Shearer et al. 2015), South Africa (Hyde et al. 1998), Thailand (Dong et al. 2020; Hyde et al. 2020), USA (Shearer 1993; Raja et al. 2009)
Fig. 1 Neohelicascus elaterascus (c, d, h, j–m from MFLU 18-1007, e–g, i, n–p from MFLU 18-0997). a, b Immersed pseudostromata with blackened ostiolar dots. c Vertical section of pseudostroma. d Structure of peridium. e–h Bitunicate asci. i–m Ascospores. (l, m in Indian Ink). n Germinated ascospore. o, p Colony on PDA (left-front, right-reverse). Scale bars: c = 50 μm, d–n = 20 μm (Dong et al. 2020)
References
Ho WH, Hyde KD, Hodgkiss JI, Yanna (2001) Fungal communities on submerged wood from streams in Brunei, Hong Kong, and Malaysia. Mycol Res 105:1492–1501
Hyde KD, de Silva NI, Jeewon R, Bhat DJ, Phookamsak R, Doilom M, Boonmee S, Jayawardena RS, Maharachchikumbura SSN, Senanayake IC, Manawasinghe IS, Liu NG, Abeywickrama PD, Chaiwan N, Karunarathna A, Pem D, Lin CG, Sysouphanthong P, Luo ZL, Wei DP, Wanasinghe DN, Norphanphoun C, Tennakoon DS, Samarakoon MC, Jayasiri SC, Jiang HB, Zeng XY, Li JF, Wijesinghe SN, Devadatha B, Goonasekara ID, Brahmanage RS, Yang EF, Aluthmuhandiram JVS, Dayarathne MC, Marasinghe DS, Li WJ, Dissanayake LS, Dong W, Huanraluek N, Lumyong S, Liu JK, Karunarathna SC, Jones EBG, Al-Sadi AM, Xu JC, Harishchandra D, Sarma VV (2020) AJOM new records and collections of fungi: 1–100. Asian Journal of Mycology 3:22–294
Hyde KD, Goh TK, Steinke TD (1998) Fungi on submerged wood in the Palmiet River, Durban, South Africa. S Afr J Bot 64:151–162
Luo J, Yin J, Cai L, Zhang KQ, Hyde KD (2004) Freshwater fungi in Lake Dianchi, a heavily polluted lake in Yunnan, China. Fungal Divers 16:93–112
Raja HA, Schmit JP, Shearer CA (2009) Latitudinal, habitat and substrate distribution patterns of freshwater ascomycetes in the Florida Peninsula. Biodivers Conserv 18:419–455
Shearer CA (1993) A new species of Kirschsteiniothelia (Pleosporales) with an unusual fissitunicate ascus. Mycologia 85:963–969
Shearer CA, Zelski SE, Raja HA, Schmit JP, Miller AN, Janovec JP (2015) Distributional patterns of freshwater ascomycetes communities along an Andes to Amazon elevational gradient in Peru. Biodivers Conserv 24:1877–1897
Tanaka K, Hirayama K, Yonezawa H, Sato G, Toriyabe A, Kudo H, Hashimoto A, Matsumura M, Harada Y, Kurihara Y (2015) Revision of the Massarineae (Pleosporales, Dothideomycetes). Stud Mycol 82:75–136
Tsui KM, Hyde KD, Hodgkiss IJ (2000) Biodiversity of fungi on submerged wood in Hong Kong streams. Aquat Microb Ecol 21:289–298
Recent Genus
1Neochlamydotubeufia
Neohelicomyces
Recent Species
Neohelicomyces submersusNeohelicomyces hyalosporus
Neohelicomyces grandisporus