Neohelicascus egyptiacus (Abdel-Wahab & Abdel-Aziz) W. Dong, K.D. Hyde & H. Zhang
Index Fungorum number: IF557924; Facesoffungi number: FoF09266
Basionym: Helicascus egyptiacus Abdel-Wahab & AbdelAziz [as ‘aegyptiacus’], Sydowia 65(1): 153 (2013)
Saprobic on decaying wood submerged in freshwater. Sexual morph: Pseudostromata 450–950 × 500–650 µm diam., comprising black fungal tissues growing in cortex of host, with 2–3(4) immersed, subglobose to triangular, dark locules, with a flattened base, and a single common ostiole. Ostiole 200–260 × 180–210 µm diam., periphysate. Periphyses 22–33 × 1.2–2.5 µm diam. Peridium of locules 46–60 µm thick in the upper region, consisting of 6–8 layers of cells of textura angularis; 20–30 µm thick in the basal region, comprising 4–7 layers of cells of textura angularis; and 180–220 µm thick at sides and angles of the base, comprising cells of textura prismatica. Pseudoparaphyses 1.2–2.5 µm wide, numerous, persistent, anastomosing above the asci, embedded in a gelatinous matrix. Asci 50–82 × 15–20 µm, 8-spored, bitunicate, fissitunicate, clavate, long pedicellate, base of the endoascus long, narrow and coiled within ectoascus, apically rounded without an obvious ocular chamber. Ascospores 27–35 × 8–14 µm, 2 – 3-seriate, subovoid to ellipsoidal, 1-septate, upper cell longer than lower cell, light brown becoming brown when mature, thin-walled, rough-walled, surrounded by a gelatinous sheath. Asexual morph: Undetermined. (Descriptions from Zhang et al. 2013)
Material examined: EGYPT, Sohag Governerate, River Nile, on submerged decaying dicotyledonous wood, 6 September 2004, leg. M. A. Abdel-Wahab, MFLU 12-0060 − ex-type living culture FWCC99.
Notes: Neohelicascus aegyptiacus is characterized by pseudostromata, with 2–3(4) immersed locules with a single common central ostiole, fissitunicate asci with a long, narrow, and coiled endoascus, and unequally two-celled, verruculose ascospores surrounded by a gelatinous sheath. Neohelicascus elaterascus has characters in common with H. aegyptiacus, including one-septate, verruculose ascospores surrounded by a gelatinous sheath. However, the former has a perithecial ascomata (Shearer 1993), while the latter has pseudostroma with 2–4 locules. Neohelicascus aegyptiacus shared the same clade with N. uniseptatus based on the phylogenetic analysis of combined LSU, SSU, ITS and TEF sequence data revealed by Dong et al. (2020).
Freshwater distribution: Egypt (Zhang et al. 2013)
Fig. 1. Helicascus aegyptiacus, holotype. A–C. Vertical section through stroma showing several locules with one common ostiole. Note: the peridium at the top and the basal part of the stroma is thinner than at the sides of the stroma. D. Magnified part of the peridium at the sides showing the textura prismatic structure. E–I. Asci at different stages of maturation, H showing coiled endoascus. Bars: A−C 50 µm, D 25 µm, E−I 10 µm. (Retrieved from https://www.researchgate.net/publication/255484499_A_modern_concept_for_Helicascus_with_a_Pleurophomopsis-like_asexual_state)
Dong W, Wang B, Hyde KD, McKenzie EHC, Raja HA, Tanaka K, Abdel-Wahab MA, Abdel-Aziz FA, Doilom M, Phookamsak R, Hongsanan S, Wanasinghe DN, Yu XD, Wang GN, Yang H, Yang J, Thambugala KM, Tian Q, Luo ZL, Yang JB, Miller AN, Fournier J, Boonmee S, Hu DM, Nalumpang S, Zhang H (2020) Freshwater Dothideomycetes. Fungal Divers 105:319–575. https://doi.org/10.1007/s13225-020-00463-5
Shearer CA (1993) A new species of Kirschsteiniothelia (Pleosporales) with an unusual fissitunicate ascus. Mycologia 85:963–969
Zhang H, Hyde KD, Abdel-Wahab MA, Abdel-Aziz FA, Ariyawansa HA, Ko TWK, Zhao RL, Alias SA, Bahkali AH, Zhou D (2013) A modern concept for Helicascus with a Pleurophomopsis-like asexual state. Sydowia 65:147–166