Trypetheliopsis Asahina, J. Jap. Bot. 13: 319 (1937).

MycoBank number: MB 5627; Index Fungorum number: IF 5627; Facesoffungi number: FoF 08084; 8 morphologically defined species (Harada 2017; Lücking et al. 2017), molecular data available for one species.

= Musaespora Aptroot & Sipman, Lichenologist 25(2): 123 (1993).

MycoBank number: MB 22430; Index Fungorum number: IF 22430; Facesoffungi number: FoF 08085.

Lichenized on bark or leaves, in tropical regions. Thallus corticate, olive-green to brownish. Photobiont Trentepohlia. Ascomata scattered or rarely pseudostromatic, erumpent to prominent, brown-black and carbonaceous or rarely with orange-red pigment, ostiolate, ostiole apical. Involucrellum present, carbonized. Excipulum dense, consisting of compressed hyphae, appearing prosoplectenchymatous in thin, bleached sections, brown to brown-black. Hamathecium comprising 0.5–0.7 µm wide paraphyses, hyaline, straight, branched and anastomosing, usually inspersed. Asci 8-spored, bitunicate, fissitunicate, cylindrical, short pedicel- late, with broad, non-amyloid ocular chamber and fluorescent cap-structures. Ascospores irregularly arranged, oval-oblong, typically slightly curved, hyaline, 1-septate, large (70–120 × 12–25 µm), with internal, needle-shaped crystals. Conidiomata campylidiiform, brown black or rarely with orange-red pigment. Conidia acrogenous, microconidia, aseptate, drop-shaped, small, hyaline, aggregated in gelatinous mass.

Chemistry: Secondary substances absent except for unidentified red pigment in the type and in T. coccinea.

Type species: Trypetheliopsis boninensis Asahina, J. Jap. Bot. 13: 319 (1937).

Notes: Trypetheliopsis was described as a monospecific genus for a corticolous lichen with pseudostromatic ascomata producing a bright, orange-red pigment and with large, 1-septate, fusiform ascospores with markedly submedian septum (Asahina 1937; Santesson 1970). The genus was largely forgotten, until Kashiwadani et al. (2009) resurrected it, considering it an earlier name for Musaespora, based on similarities (in particular the orange-red pigment) with Musaespora coccinea.