Parameliola acaciae Hongsanan & K.D. Hyde, sp. nov.
Index Fungorum number: IF 551928, Facesoffungi number: FoF 01963, Fig. 1
Etymology: acaciae referring to the host.
Holotypus: MFLU15–0378

Hyperparasite on the surface of hyphae of Meliola thailandicum. Conidiomata 84 – 88 μm diam. (x̄ =85 μm, n = 10), superficial, solitary or gregarious, globose to subglobose, attached to the superficial hyx̄ phae of Meliola thailandicum, ostiole absent, thin-walled, brown to dark brown. Setae 5μm diam., aseptate, brown to reddish brown, pale brown to hyaline at the apex. Peridium 10μm (x̄ = 8 μm, n = 10), comprising 2 layers of textura angularis, inner layer hyaline, outer layer dark brown. Hamathecium lacking pseudoparaphyses. Conidiophores reduced to conidiogenous cells. Conidiogenous cells 4 – 5 × 1 – 2 μm (x̄ = 4.5 × 1.5 μm, n = 5) wide, holoblastic in cavity of conidiomata, cylindrical, hyaline, smooth-walled. Conidia 7 – 10 × 3 – 4 μm (x̄ = 9 × 3.5 μm, n = 10), borne singly at the apex of the conidiophore, cylindrical to oblong, both ends broadly rounded, aseptate, hyaline, smooth-walled.

Material examined: THAILAND, Chiang Rai, Mueang, Agricultural Research Center, on living leaves of Acacia auriculiformis A. Cunn. ex Benth. (Fabaceae), 23 January 2015, S. Hongsanan (MFLU 15–0378; KIB, isotype).

Notes: Parameliola acaciae is similar to P. dimocarpi, however, it differs in having cylindrical to oblong ascospores, which are slightly larger than those of P. dimocarpi. Parameliola acaciae was found among the colonies of Meliola thailandicum growing on dead leves of Acacia auriculiformis, while Parameliola dimocapi was found among the colonies of Meliola thailandicum growing on leaving leaves of Dimocarpus longan (Hongsanan et al. 2015). Phylogenetic analyses indicate that Parameliola. acaciae is closely related to the type species of Parameliola, but is a distinct species, therefore the placement of Parameliola in Pleosporales is supported.

Fig. 1 Parameliola acaciae (holotype) a, b Conidiomata developing as hyperparasites on the thallus or hyphae of Meliola thailandicum c Hyphae of M. thailandicum with hyphopodia d Section through conidiomata in 10 % lactic acid e Conidiogenous cell f Conidia. Scale bars: a, b = 100 μm, c = 10 μm, d = 50 μm, e, f = 5 μm.