Gesasha
peditatus
Abdel-Wahab & Nagahama, Nova Hedw. 92: 502 (2011)
Sordariomycetes, Subclass Hypocreomycetidae
Microascales
Halosphaeriaceae
Gesasha Abdel-Wahab & Nagahama, Nova Hedw. 92: 501 (2011)
Type species:
Gesasha peditatus Abdel-Wahab & Nagahama, Nova Hedw. 92: 502 (2011)
Index Fungorum number: Faceoffungi number:
Sexual morph: saprobic, ascomata 200–320 × 260–320 μm, subglobose, elongate, ovate, hyaline to light brown, coriaceous, immersed or erumpent, solitary, ostiolate with a long hyaline neck. Neck 300–800 × 60–90 μm, hyaline, cylindrical, periphysate. Periphyses up to 22 μm in length and 0.5 μm in width. Peridium 20–24 μm wide, consisting of 7–9 layers of thick-walled cells with large lumina, forming textura angularis, cells hyaline except the first outside layer which is brown in color. Catenophyses present. Asci 100–150 × 20–30 μm, unitunicate, clavate with a long stalk, with apical thickening and pore, apically truncate with cytoplasmic retraction, persistent, with eight overlapping biseriate ascospores, developing in a hymenium at base of ascoma venter. Ascospores 18–30 × 9–16 μm, one-septate, subglobose, ellipsoidal or foot-like, with sub-median septum, distoseptate, not constricted at the septa, thick-walled, the walls being 2–2.5 μm thick, hyaline becoming light brown with age, with polar to sub-apical amorphous, ephemeral appendages, smooth. Asexual morph: Undetermined (Description based on Abdel-Wahab & Nagahama (2011)).
Key references:
Abdel-Wahab MA, Nagahama T (2011) Gesasha (HalosphaerialesAscomycota), a new genus with three new species from the Gesashi mangroves in Japan. Nova Hedwigia 92: 497-512.
Campbell J, Anderson JL, Shearer CA (2003) Systematics of Halosarpheia based on morphological and molecular data. Mycologia 95: 530-552.
Jones EBG, Suetrong S, Sakayaroj J, Bahkali AH, Abdel-Wahab MA, Boekhout T, Pang KL (2015) Classification of marine Ascomycota, Basidiomycota, Blastocladiomycota and Chytridiomycota. Fungal Diversity 73: 1-72.
Jones EBG, Ju WT, Lu CL, Guo SY, Pang KL (2017) The Halosphaeriaceae revisited. 60: 453-468l.
Pang KL, Vrijmoed LLP, Kong RYC, Jones EBG (2003) Polyphyly of Halosarpheia (Halosphaeriales, Ascomycota): implications on the use of unfurling ascospore appendages as a systematic character. Nova Hedwigia 77: 1-18.
Shearer CA (1989) Aniptodera (Halosphaeriaceae) from wood in freshwater habitats. Mycologia 81: 139-146.
Maharachchikumbura SSN, Hyde KD, Jones EBG, Mckenzie EHC, Huang SK, Abdel-Wahab MA et al. (2015) Towards a natural classification and backbone tree for Sordariomycetes. Fungal Diversity 72: 199-299.
Volkmann-Kohlmeyer B, Kohlmeyer J (1994) A new Aniptodera (Ascomycotina) from salt march Juncus. Botanica Marina 37: 109-114.
Key to species of Gesasha:
- Ascospores one-septate.................................................................................................................................................................2
- Ascospores unicellular....................................................................................................................................................................3
2. Ascospores 18–30 × 9–16 μm, subglobose, ellipsoidal or foot-like, with sub-median septum, distoseptate, not constricted at the septa, thick-
walled, hyaline becoming light brown with age, with polar to sub-apical amorphous, ephemeral appendages, smooth......................G. peditatus
- Ascospores 16–18 × 8–10 μm, hyaline, ellipsoidal, one-septate, not constricted at the septum, without appendages.................G. mangrovei
- Ascospores 8–10(11) × 5–6(7) μm, unicellular, subglobose, ellipsoidal or oval, without appendages, hyaline becoming light brown with age...........................................................................................................................................................................G. unicellularis
Image: Gesasha spp. (a–c) G. peditatus (a) Vertical section through ascoma (b) Apical part of the ascus (c) Ascospore (d–f) G. unicellularis (d) Vertical section through ascoma (e) Apical part of the ascus (f) Ascospore (g–i) G. mangrovei. (g) Vertical section through ascoma. (h) Apical part of the ascus (i) Ascospore. Bars a, d, g=50 μm; b–c, e–f, h–i=5 μm. (Photo plate from Jones et al. 2015).