Nigrovothelium Lücking, M.P. Nelsen & Aptroot, in Lücking et al., Lichenologist 48(6): 757 (2016)
Index Fungorum number: IF 816875; Facesoffungi number: FoF 08804, 3 morphological species (Species Fungorum 2021), 2 species with molecular data.
Thallus corticate. Sexual morph: Ascomata usually single but often crowded and irregularly confluent, sessile, ovoid, not in pseudostromata. Ostiole apical. Hamathecium hyaline, clear, filaments thin, anastomosing paraphysoids, often inspersed with oil. Asci clavate. Ascospores transversely 3-septate, with distinct endospore formation creating diamond shaped lumina (astrothelioid), hyaline. Asexual morph: Unknown. Chemistry. Thallus and ascomata UV−, K−. TLC: no substances detected. (Adapted from Lucking et al. 2016).
Type species: Nigrovothelium tropicum (Ach.) Lücking, M.P. Nelsen & Aptroot
Notes: Nigrovothelium was introduced by Lücking et al. (2016) with N. tropicum as type species. Nigrovothelium resembles other genera such as Pseudopyrenula and Astrothelium in having astrothelioid ascospores and Bathelium in having exposed, dark ascomata. Nigrovothelium is unique in having ascomata prominent to sessile, fully exposed and black, solitary but usually crowded, lacking pigments; ascospores 3-septate (Aptroot and Lucking 2016). Nigrovothelium is closely related to Polymeridium but differs from that genus in the corticate thallus and astrothelioid ascospores. Nigrovothelium is a well-supported genus in Trypetheliaceae.