Sulcatistroma A.W. Ramaley, Mycotaxon 93: 140 (2005)
Hypocreomycetidae, Hypocreales genera incertae sedis
Index Fungorum number: IF 28974; 1 morphological species; 1 species with sequence data.
Saprobic on leaves. Sexual morph: Ascostromata discrete, multi-loculate, erumpent through leaf epidermis, ellipsoidal, rarely circular. Ascomata perithecial, immersed, formed in stroma, subglobose, dark brown, ostiole with hyaline periphyses. Peridium membranaceous, composed of hyaline to brown cells of textura angularis. Paraphyses numerous, septate, slightly constricted at the septa, unbranched, tapering to a rounded apex. Asci 8-spored, unitunicate, clavate, short pedicellate. Ascospores bi-seriate, hyaline, allantoid with rounded ends, aseptate, smooth-walled. Asexual morph: Hyphomycetous. Conidiophores arising from aerial hyphae, erect, inflated at the base. Phialides monophialidic, smooth-walled, hyaline, cylindrical, unbranched or with sympodial conidiogenous cells. Conidia hyaline to pale orange, ellipsoidal to allantoid, aseptate, smooth-walled, with rounded ends (copied from Huang et al. 2021).
Type species: Sulcatistroma nolinae A.W. Ramaley, Mycotaxon 93: 140 (2005)
Notes: The monotypic genus Sulcatistroma has ellipsoidal ascostromata, clavate asci, allantoid ascospores and ellipsoidal to allantoid conidia (Ramaley 2005). This genus is similar to the sexual morph of Diatrype (Xylariales), differing from Sulcatistroma in having sympodial conidiogenous cells, whereas Diatrype has percurrently proliferating conidiogenous cells (Ramaley 2005). Initially, Sulcatistroma was accepted as a member of Calosphaeriales based on its spicate clusters of asci (Ramaley 2005), and later it was included in Calosphaeriaceae (Lumbsch and Huhndorf 2010; Maharachchikumbura et al. 2015, 2016; Wijayawardene et al. 2018). Vu et al. (2019) analyzed ITS sequence data for ex-type strain Sulcatistroma nolinae (CBS 117709). This strain is more closely related to members of Nectriaceae (Hypocreales) (Fig. 1 in Huang et al. (2021)). Sulcatistroma has similar features to Nectriaceae species, such as clavate asci, aseptate, allantoid ascospores and phialophora-like asexual morphs, but does not have the red ascomata which is characteristic of Nectriaceae (Hirooka et al. 2012). Huang et al. (2021) placed Sulcatistroma in Hypocreales genera incertae sedis pending phylogenetic data (copied from Huang et al. 2021).
Species illustrated in this entry:
Sulcatistroma nolinae A.W. Ramaley