Aulographales » Aulographaceae

Thyriopsis

Thyriopsis Theiss. & Syd., Annls mycol. 13(3/4): 369 (1915).

Index Fungorum number: IF 5468; Facesoffungi number: FoF 07950, 2 morphological species (Species Fungorum 2022), no molecular data available.

Saprobic on needles, forming blackened spots on the surface. Superficial hyphae not observed. Sexual morph: Thyriothecia scattered or sometimes in linear rows, subcuticular, flattened, opening by linear fissures, sometimes Y-shaped, composed of the yellow to brown loose cells, easily broken. Peridium at the side composed of dark brown elongate cells, upper layer dissolving to release asci which are vertical in the thyriothecium. Hamathecium lacking pseudoparaphyses. Asci 8-spored, bitunicate, thick-walled, globose to obovoid, apedicellate. Ascospores fasciculate, ellipsoidal, 2-celled, cells of roughly equal size, rounded at the ends, highly constricted at the septa, hyaline, some yellowish-brown. Asexual morph: Pycnidia black, amphigenous, subcuticular, roundish to elongate, covered with a layer of isodiametric, brownish, thick-walled cells, opening by clefts. Conidiophores originating from a thin layer of hyphae next to substratum, hyaline, cylindrical to obclavate, becoming septate. Conidia hyaline, oval to cylindrical (von Arx & Müller 1975, Hongsanan et al. 2014).

Type species: Thyriopsis halepensis (Cooke) Theiss. & Syd.

Notes: Thyriopsis is characterised by scattered, subcuticular, flattened thyriothecia, globose to obovoid asci and fasciculate, ellipsoidal, two-celled ascospores. The asexual morph is characterised by black, amphigenous, subcuticular, roundish to elongate pycnidia, hyaline, cylindrical to obclavate conidiophores and hyaline, oval to cylindrical conidia. Van der Byl (1929) added the second species T. proteae collected from leaves of Protea scrabra in South Africa. Marasas (1969) added the third species T. sphaerospora isolated from leaves of Eucalyptus in South Africa. Arx and Müller (1975) placed Thyriopsis in Leptopeltidaceae based on morphology such as subcuticular thyriothecia and brown ascospores. Lumbsch and Huhndorf (2010) transferred Thyriopsis to the Asterinaceae. Thyriopsis differs from Asterina in having thyriothecia that lack a fibrous dark brown margin, globose asci, dark brown elongate peridium cell and hyaline ascospores without surface mycelia bearing appressoria (Hongsanan et al. 2014). Hongsanan et al. (2014) re-examined the holotype specimen of T. halepensis (K 164016) and transferred Thyriopsis to Aulographaceae based on morphology especially elongate thyriothecia, globose asci, and hyaline ascospores without surface mycelia bearing appressoria. Thyriopsis is morphologically a distinct genus in Aulographaceae but more collections are needed to confirm this taxonomic placement.

 

About Dothideomycetes

The website Dothideomycetes.org provides an up-to-date classification and account of all genera of the class Dothideomycetes.

Mushroom Research Foundation

Contact



Published by the Mushroom Research Foundation 
Copyright © The copyright belongs to the Mushroom Research Foundation. All Rights Reserved.