Schizothyriaceae Höhn. ex Trotter, Sacc., D. Sacc. & Traverso [as ‘Schizothyrieae‘], in Saccardo, Syll. fung. (Abellini) 24(2): 1254 (1928).
MycoBank number: MB 81266; Index Fungorum number: IF 81266; Facesoffungi number: FoF 01932, 64 species.
Epiphytic, pathogenic or saprobic on fruits and leaves or twigs of various plants, epiphyllous or hypophyllous on leaves, visible as rounded, small to medium, dark grey to black dots on the host surface, lacking superficial or subcuticular vegetative hyphae expanding on host surface. Sexual morph: Ascomata scattered, solitary to gregarious, superficial, flattened, circular to ellipsoid, light brown or dark brown to black, transparent to opaque, scutate to dimidiate, or orbicular, glabrous, uni-loculate, lacking ostioles, or opening by splitting of the upper wall. Peridium thin-walled, poorly-developed at the base, comprising 3 types of peridial structure; type I: composed of 2–3- layered, light brown to dark brown, or black cells of textura angularis to textura globulosa; type II: composed of thin, pale brown to pale grey, transparent, membranous cells; type III: composed of brown to reddish brown, septate, roughly coarse, branching, botryose elements, or loosely packed hyphae. Hamathecium comprising net-like or pseudoparaphysoid-like filaments. Asci 4–8-spored, bitunicate, globose to subglobose, obovoid to clavate, sessile to subsessile, or short pedicellate, apically rounded broad, with an ocular chamber. Ascospores overlapping 3–5-seriate, oblong to ellipsoidal, or claviform, hyaline to subhyaline, septate, constricted at the septum, thin- to thick- walled, smooth to rough, with small guttules. Asexual morph: Hyphomycetous (see Batzer et al. 2008).
Type – Schizothyrium Desm.
Notes – The concept of Schizothyriaceae was originally described as “exciple depressed on cuticle, superficial, membranous, irregular fringed when mature” (Saccardo 1928). Schizothyriaceae is a poorly understood family comprising many doubtful genera due to the lack of molecular data. Hyde et al. (2013) re-circumscribed the genera in Schizothyriaceae based on study of type materials as well as representative specimens and accepted 15 genera viz. Amazonotheca, Chaetoplaca, Henningsiella, Hexagonella, Kerniomyces, Lecideopsella, Linopeltis, Mendogia, Metathyriella, Mycerema, Myriangiella, Neopeltella, Orthobellus, Plochmopeltis and Schizothyrium (= Zygophiala, hyphomycetous asexual morph). Ariyawansa et al. (2013) tentatively placed Hysteropeltella in Schizothyriaceae. Phookamsak et al. (2016) revised the taxonomic placement of genera in Schizothyriaceae based on the study of their type material and representative specimens and also provided detailed taxonomic descriptions of these genera. Phookamsak et al. (2016) accepted only five genera in Schizothyriaceae viz. Hexagonella, Lecideopsella, Mycerema, Plochmopeltis and Schizothyrium. Kerniomyces, Metathyriella and Myriangiella were treated as doubtful genera due to the lack of their type materials and taxonomic literature (Phookamsak et al. 2016). Wijayawardene et al. (2018) tentatively placed these three genera in Schizothyriaceae pending future studies and listed nine genera in this family. Doilom et al. (2018) included Vonarxella in Schizothyriaceae based on the type study. There are presently ten genera listed in Schizothyriaceae, viz. Amazonotheca, Hexagonella, Kerniomyces, Lecideopsella, Metathyriella, Myriangiella, Mycerema, Plochmopeltis, Schizothyrium and Vonarxella (Doilom et al. 2018, Wijayawardene et al. 2018).
The taxonomic placement of Schizothyriaceae has a long history. A detailed literature review was provided by Phookamsak et al. (2016). The phylogenetic placement of Schizothyriaceae was determined by Batzer et al. (2005, 2008) and Crous et al. (2007, 2009) based on Schizothyrium pomi and its asexual morph, Zygophiala. Phylogenetic analyses have shown that Schizothyriaceae belongs to Capnodiales, allied to Mycosphaerellaceae (Batzer et al. 2005, 2008, Crous et al. 2007, 2009, Yang et al. 2010). Evolutionary relationships of the higher-ranking classification using divergence times and molecular dating also support Schizothyriaceae in Capnodiales (Hongsanan et al. 2016, Liu et al. 2017a).