Dwiroopa Subram. & Muthumary, Proc. Indian Acad. Sci., Pl. Sci. 96(3): 196 (1986)
MycoBank number: MB 11077; Index Fungorum number: IF 11077; Facesoffungi number: FoF 09181; 3 morphological species (Species Fungorum 2020), 2 species with sequence data.
Type species – Dwiroopa ramya Subram. & Muthumary
Notes – Members of Dwiroopa resemble Harknessia in having uni- to multiloculate, thick- walled, immersed to semi-immersed conidiomata, becoming erumpent, dark brown and aseptate, thick-walled macroconidia with holoblastic conidiogenesis, with conidiogenous cells bearing periclinal thickenings. Dwiroopa is distinguished from Harknessia in having distinct, holoblastic conidiogenesis, thick-walled conidiogenous cells and broadly spaced several longitudinal striations in the macroconidia, lacking a basal appendage and showcasing a dark scar with minute marginal frills at the conidial connection. Harknessia is distinct from Dwiroopa in having macroconidia that are smooth-walled or have closely spaced longitudinal raised bands on only one side and usually with a true basal appendage. Furthermore, Dwiroopa produces three different kinds of conidia viz. macroconidia, mesoconidia and phialoconidia (Farr & Rossman 2003), which are not produced in Harknessia. Farr & Rossman (2003) redescribed Dwiroopa ramya and designated it as a lectotype and also introduced Harknessia lythri as Dwiroopa lythri in Dwiroopa based on morphological similarities.
Figure 100 – Dwiroopa ramya (redrawn from Subramanian & Muthumary 1986). a Vertical section of conidioma. b Conidia. c-f Stages in the development of macroconidia. g Paraphysis-like structures. h Meso-conidia, note, developing and mature conidia. i Phialides with developing phialoconidia. j Phialoconidia. Scale bars: a = 100 μm, b = 20 μm, c, d, f-i = 10 μm, e, j = 5 μm.