Triangularia – Facesoffungi number: FoF 13547

Triangularia Boedijn, Ann. Mycol. 32: 302 (1934)

        Synonym: Apiosordaria Arx & W. Gams, Nova Hedwigia 13: 201. 1967.

MycoBank number: MB 5534; Index Fungorum number: IF 5534; Facesoffungi number: FoF 13547; 14 morphological species (Wang et al. 2019a), 9 species with sequence data.

Sexual morph Ascomata ostiolate or non-ostiolate, often superficial, sometimes semi-immersed to immersed, solitary or aggregated, globose to subglobose, ovoid, or obpyriform to ampulliform, glabrous or with hypha-like or seta-like hairs; neck papillate, sometimes with rigid, agglutinated, cylindrical, septate, thick hairs, sometimes striate with 5–8 striations. Ascomatal wall membranaceous to coriaceous, translucent, semitranslucent, or opaque, textura angularis to textura globulosa, sometimes composed of areoles of textura angularis. Periphyses absent or present. Paraphyses usually present, hyaline, filiform or filiform-ventricose. Asci unitunicate, four-, eight-, or multi-spored, cylindrical to elongated clavate or fusiform, short or long stipitate, without or with an inconspicuous or thick apical ring, evanescent or persistent until ascospores mature. Ascospores one- or two-celled. One-celled ascospores uniseriate, at first hyaline, becoming yellowish, olivaceous to brown-black, ellipsoidal, smooth-walled, with an apical germ pore; gelatinous cauda at each end. Two-celled ascospores uniseriate, biseriate, triseriate, or irregularly arranged; upper cell olivaceous brown, brown, or dark brown, ellipsoidal, ovoid, fusiform, navicular, or conical and triangular in lateral, smooth-walled, or spinulose to warty, with an apical or subapical pore, rarely 1-septate; lower cell short or long, hyaline to pale brown, occasionally brown, elongate fusiform, cylindrical, conical, triangular to hemispherical, rarely early evanescent, frequently collapsing, rarely up to 3-sepate; gelatinous appendages absent or present. Asexual morph absent or present. Conidiophores micronematous, reduced to conidiogenous cells. Conidiogenous cells intercalary or occasionally terminal, sometimes phialidic, originating lateral or terminal peg-like structure with a flaring collarette. Conidia blastic, single-celled, hyaline, globose to subglobose or pyriform, smooth-walled, usually with a truncated base and a rounded apex.

Type species – Triangularia bambusae (J.F.H. Beyma) Boedijn

Notes – Triangularia was introduced by Boedijn and defined by cylindrical or clavate asci with a thickened apical ring and 2-celled smooth ascospores, with a larger, pigmented and conical to triangular upper cell and a smaller, paler or hyaline and triangular to hemisphaerical lower cell, without gelatinous appendages (Guarro & Gene 1988). However, phylogenetic analysis in Wang et al. (2019a) did not support the morphologically defined genus concept of Triangularia. Therefore, this genus is re-defined which includes morphologically diverse species. Triangularia species are usually isolated from soil and plant debris and occasional from aquatic sediments, generally from warm places (Guarro & Cano 1988).

Key to species of Triangularia

Species