Dwiroopaceae K.V. Xavier, A.N. KC, J.Z. Groenew., Vallad & Crous, Fungal Systematics and Evolution 4: 38 (2019)
Index Fungorum number: IF830873; 3 species.
Saprobic or pathogenic on leaves, twigs, branches and fruits. Sexual morph: Undetermined. Asexual morph: Coelomycetous. Conidiomata pycnidial, immersed to semi-immersed, erumpent, solitary, uni- to multiloculate, scattered, globose, black, ostiolate or lacking ostioles. Peridium thick-walled, comprising wall of 3–6 layers of pale brown cells of textura angularis. Conidiophores lining the innermost wall layer of peridium, mostly reduced to conidiogenous cells. Conidiogenous cells holoblastic, ampulliform to subcylindrical, hyaline to pale brown, sometimes proliferating percurrently at apex. Conidia unicellular, solitary, truncate at base, of three types: Macroconidia solitary, dark brown, aseptate, granular at surface, guttulate, thickwalled, broadly ellipsoid to obovoid, with longitudinal striations running along the length of conidia. Mesoconidia hyaline to pale brown, ellipsoid, aseptate and microconidia ellipsoid, hyaline, aseptate (adapted from Xavier et al. 2019).
Type genus – Dwiroopa Subram. & Muthumary
Notes – Castlebury et al. (2002) placed Harknessia and Dwiroopa in Diaporthales based on LSU phylogeny. Subsequently, Crous et al. (2012d) established Harknessiaceae to include species of Harknessia with wuestneia-like sexual morphs in Diaporthales. Dwiroopaceae was established by Xavier et al. (2019) to accommodate a monotypic genus Dwiroopa including three species in Diaporthales. Dwiroopaceae species share closer characters with taxa of Harknessiaceae and have to sister relation with Harknessiaceae in a multigene phylogenetic analysis.
Ecological and economic significance of Dwiroopaceae
Species of Dwiroopaceae are saprobes and pathogens in terrestrial habitats. Dwiroopa ramya is a saprobe on dead twigs in India (Subramanian & Muthumary 1986), while D. lythri is a pathogen on a noxious weed purple loose strife in North America (Farr & Rossman 2001). Dwiroopa punicae represents a severe pathogen of Punica granatum across the southeastern USA causing up to 100% fruit damage (Xavier et al. 2019).