Fungalpedia – Note 1037, Pyrenotrichaceae
Pyrenotrichaceae Zahlbr.
Citation when using this data: Tian Q et al. 2021 (in prep.) – Fungalpedia, Ascomycota.
Index Fungorum, Facesoffungi, MycoBank, GenBank.
Classification: Chaetothyriales, Chaetothyriomycetidae, Eurotiomycetes, Pezizomycotina, Ascomycota, Fungi
Thallus corticolous or foliicolous, composed of densely arranged, but not conglutinated, appressed filaments, filaments formed by unbranched or falsely branched photobiont threads wrapped in a sheath of fungal hyphae, hyphae branched and anastomosing, formed by elongate, often strongly curved and terminally inflated, pale brownish cells. Photobiont cyanobacterial. Sexual morph: Ascomata perithecioid, sessile or immersed between thallus filaments, globose to pear-shaped with a short neck, glabrous. Ostiole indistinct, with rather long, hyaline periphysoids. Excipulum thin, paraplectenchymatous, composed several layers of narrow to broader, thin-walled to thick-walled and hyaline to strongly pigmented cells. Involucrellum absent. Hamathecium aparaphysate, J+, KI+. Asci fissitunicate, broadly clavate to saccate, J-, KI-, but lumen I+ yellow and KI+ pale yellow. Ascospores 8-spored, transversally septate to muriform, pale to dark grayish brown. Asexual morph: Undetermined.
Notes: Engler & Prantl (1926) established Pyrenotrichaceae Zahlbr. to accommodate Pyrenothrix Riddle with two foliicolous species presently accepted (Riddle 1917, Herrera-Campos et al. 2005). Henssen (1964) referred Pyrenothrix to Pleosporales because it has perithecia. Eriksson (1981) contradicted Henssen’s placement for this genus and suggested Pyrenothrix was closely related to the sooty molds, in particular Coccodiniaceae, now placed in Chaetothyriales by filamentous thallus and perithecia. Herrera-Campos et al. (2005) proposed including the genus in Chaetothyriales. Molecular sequences for species of Pyrenotrichaceae are lacking, and therefore we place this family in Chaetothyriales, consistent with the opinion of Herrera-Campos et al. (2005), Lücking (2008) and Wijayawardene et al. (2020), pending further study.
Type genus: Pyrenothrix Riddle, Bot. Gaz. 64: 513 (1917).
References
Eriksson OE. 1981 – The families of bitunicate ascomycetes. Nordic Journal of Botany 1(6), 800.
Henssen A. 1964 – Was ist Pyrenothrix nigra? Ber Deutsch Bot Gesell 77, 317–322.
Lücking R. 2008 – Foliicolous Lichenized Fungi. Flora Neotropica Monograph 103, 1– 866.
Entry by
Qing Tian, Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai 57100, Thailand, School of Science, Mae Fah Luang University, Chiang Rai 57100, Thailand
Published online 16 December 2021