Dothideomycetes families incertae sedis » Dothideomycetes genera incertae sedis


Wettsteinina Höhn.


Saprobic or hemibiotrophic on submerged wood in freshwater or plant leaves and stems in terrestrial habitats. Sexual morph: Ascomata small-sized, scattered, immersed with a protruding broad papilla. Peridium composed of several layers of large, polygonal, thin-walled cells. Pseudoparaphyses deliquescing at maturity. Asci bitunicate, fissitunicate, subglobose to obpyriform, sessile, with a small ocular chamber, thick-walled. Ascospores 2–4-seriate, broadly clavate, hyaline and become pale brown when mature, septate, smooth, surrounded by a hyaline gelatinous sheath (Zhang et al. 2012). Asexual morph: Undetermined.


Type species: Wettsteinina gigantospora (Rehm) Höhn.


Notes: Wettsteinina is characterized by thick-walled, obpyriform asci, asymmetrical ascospores, and lack pseudoparaphyses at maturity (Zhang et al. 2012). The placement of Wettsteinina is confused because of lack of sequences of the type species, W. gigantospora. Wettsteinina was placed in Pleosporaceae based on its “pleospora-type” centrum (Shoemaker and Babcock 1987), later excluded from Pleosporaceae based on molecular data of three species, but not assigned to other families (Kodsueb et al. 2006). Wettsteinina is placed in Dothideomycetes genera incertae sedis by Wijayawardene et al. (2018, 2020). The molecular data of freshwater species W. moniliformis Van Ryck. & Aptroot and W. niesslii E. Müll. are unavailable. They can be distinguished from each other by the size of ascospores (see key below). (Dong et al. 2020)


List of freshwater Wettsteinina species

Wettsteinina moniliformis Van Ryck. & Aptroot, Nova Hedwigia 73(1–2): 164 (2001)

Freshwater distribution: Denmark (Van Ryckegem and Aptroot 2001)

Wettsteinina niesslii E. Müll., Sydowia 4(1-6): 204 (1950)

Freshwater distribution: England (Ingold 1955; Apinis et al. 1972; Taligoola et al. 1972), USA (Shearer 1972)


Key to freshwater Wettsteinina species

1. Ascospores with pointed ends, 55–70 × 9.5–12 μm......................... W. niesslii

1. Ascospores with rounded ends, 19–23 × 7–9 μm..................... W. moniliformis


Fig. 135

Fig 1 Wettsteinina spp. a–e W. niesslii (redrawn from Scheuer (1995), lectotype). a Longitudinal section of ascoma. b Ascus and interascal filaments. c–e Young, mature and senescent ascospores. f–h W. moniliformis (redrawn from (Van Ryckegem and Aptroot 2001), holotype, GENT). f Ascus. g Ascospore. h Pseudoparaphyses filament. Scale bars: a = 50 μm, b–e = 20 μm, f, g = 10 μm, h = 20 μm (Dong et al. 2020)



Apinis AE, Chester CGC, Taligoola HK (1972) Microfungi colonizing submerged standing culms of Phragmites communis Trin. Nov Hedwigia 23:473–480

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 X-D, Wang G-N, Yang H, Yang J, Thambugala KM, Tian Q, Luo Z-L, Yang J-B, Miller AN, Fournier J, Boonmee S, Hu D-M, Nalumpang S, Zhang H (2020) Freshwater Dothideomycetes. Fungal Divers 105:319–575.

Ingold CT (1955) Aquatic ascomycetes: Further species from the English Lake district. Trans Br Mycol Soc 38:157–168.

Kodsueb R, Dhanasekaran V, Aptroot A, Lumyong S, McKenzie EHC, Hyde KD, Jeewon R (2006) The family Pleosporaceae: Intergeneric relationships and phylogenetic perspectives based on sequence analyses of partial 28S rDNA. Mycologia 98:571–583.

Shearer CA (1972) Fungi of the Chesapeake Bay and its tributaries. III. The distribution of wood-inhabiting ascomycetes and fungi imperfecti of the Patuxent River. Am J Bot 59:961.

Shoemaker RA, Babcock CE (1987) Wettsteinina. Can J Bot 65:373–405.

Taligoola TK, Apinis AE, Chesters CGC (1972) Microfungi colonizing collapsed aerial parts of Phragmites communis Trin. in water. Nov Hedwigia 23:465–472

Wijayawardene NN, Hyde KD, Al-ani LKT, Tedersoo L, Haelewaters D, Rajeshkumar KC, Zhao R, Aptroot A, Leontyev D V, Ramesh K, Tokarev YS, Dai D, Letcher PM, Steven L, Ertz D, Lumbsch HT, Kukwa M, Issi V, Madrid H, Phillips AJL, Selbmann L, Walter P, Horváth E, Bensch K, Kirk P, Raja HA, Radek R, Papp V, Dima B, Ma J, Malosso E, Takamatsu S, Rambold G, Gannibal PB, Triebel D, Gautam AK, Avasthi S, Suetrong S, Timdal E, Fryar SC, Delgado G, Réblová M, Doilom M, Dolatabadi S, Humber RA, Kodsueb R, Sánchez- I, Goto BT, Silva DKA, Souza FA De, Silva GA, Silva IR, Błaszkowski J, Jobim K, Maia LC, Barbosa FR, Fiuza PO, Divakar PK, Shenoy BD, Castañeda-ruiz RF, Papizadeh M, Heredia G, Bakhshi M, Boehm E, Youssef N, Vincent P, Lawrey JD, Santiago ALCMDA, Jadson DP, Souza-motta CM, Firmino AL, Tian Q, Monteiro JS, Grossart H, Suija A, Etayo J, Tsurykau A, Kuhnert E, Mungai P, Damm U, Li Q, Zhang H, Boonmee S, Lu Y, Becerra AG, Brearley FQ, Motiejūnaitė J, Khare R, Gaikwad S, Siril DA, Tang L, He M, Flakus A, Zhurbenko MP, Mckenzie EHC, Bhat DJ, Kui-liu J, Raza M, Nassonova ES, Prieto M, Jayalal RGU, Yurkov A, Schnittler M, Shchepin ON, Yuri K, Liu P, Cavender JC, Kang Y, Zhang L, Xu R, Li Y, Monika C, Ekanayaka AH, Wen T, Lateef AA, Pereira OL, Navathe S, Hawksworth DL, Fan X, Dissanayake LS (2020) Outline of Fungi and fungus-like taxa. Mycosphere 11:1–367.

Wijayawardene NN, Hyde KD, Lumbsch HT, Liu JK, Maharachchikumbura SSN, Ekanayaka AH, Tian Q, Phookamsak R (2018) Outline of Ascomycota: 2017. Fungal Divers 88:167–263.

Van Ryckegem G, Aptroot A (2001) A new Massarina and a new Wettsteinina (Ascomycota) from freshwater and tidal reeds. Nov Hedwigia 73:161–166.

Zhang Y, Crous PW, Schoch CL, Hyde KD (2012) Pleosporales. Fungal Divers 53:1–221.


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