Eumela Syd., Annls mycol. 23(3/6): 335 (1925)
Parasitic on living leaves of Chiococca racemosa, colonies large, superficial, irregular, black, with superficial mycelium forming a network, hypophyllous, dark brown outwardly. Sexual morph: Ascomata sessile, small, superficial, solitary, scattered, globose to subglobose, black, papillate, surrounded by brown to dark brown appendaged, undulate hyphae, branched, septate. Peridium comprising brown cells of textura angularis to subglobosa, lacking pseudoparaphyses. Hairy hyphae longer than 100 μm, pale brown to dark brown, simple, unbranched, numerous, straight or curved, septate, gradually paler upwards, flexuous, slightly constricted at the septa, apex rounded. Asci 8-spored, bitunicate, broadly clavate, cylindrical to nearly ellipsoidal, sessile, slightly thickened and bluntly rounded near the apex. Ascospores multi-seriate, overlapping, oblong to ovoid oblong, ends rounded, 1-septate, slightly constricted at the septum, hyaline, smooth-walled. Asexual morph: Undetermined.
Type species – Eumela chiococcae Syd.
Notes – The monotypic genus Eumela was introduced by Sydow (1925) for Eumela chiococcae found on living leaves of Chiococca racemosa in Costa Rica. Eumela is closely associated to Episphaerella Petr., Eudimeriolum Speg. and Lasiostemma Theiss. & Syd., but differs from these genera in having hyphae penetrating the epidermal cells, stromata as well as guard cells forming haustoria. The genus Episphaerella form extensive mycelium all over leaf tissues. The hyphae of Eudimeriolum are totally superficial or penetrating trichomes. The hyphae of Lasiostemma form a discrete hyphal layer in or under the cuticle (Farr 1984, Barr 1987). The asexual morph is unknown. The genus Eumela was previously placed in Pseudoperisporiaceae (Lumbsch & Hundorf 2010, Hyde et al. 2013, Kirk et al. 2013). However, Boonmee et al. (2017) treated Eumela as a genus in Dothideomycetes genera incertae sedis. In this study, we examined the syntype of Eumela chiococcae and illustrate the morphological characters. It seems that species of Eumela resemble those of Antennulariella, by superficial subglobose to globose ascomata with hyphal appendages, aparaphysate hamathecium and clavate to ellipsoidal 8-spored asci. The genus Eumela is therefore transferred to Antennulariellaceae based on the sexual morph characters, numerous aerial mycelium colonies and ascospores features