Angularia R. Xu, Phukhams. & Y. Li, gen. nov.
Index Fungorum Number: IF 843307; MycoBank Number: MB 843307; Facesoffungi Number: FoF 16086
Etymology – referring to the angular peridium of the type species.
Saprobic on decaying wood or herbaceous plant material in terrestrial habitats. Sexual morph: Undetermined. Asexual morph: Conidiomata pycnidial, solitary, sometimes aggregated, uniloculate, immersed in host substrate, dark brown to brown, globose, coriaceous. Ostioles absent. Conidiomatal wall thick-walled, multilayered, scleroplectenchymatous cells thick at the base, composed of textura angularis, lined with a thick hyaline layer bearing conidiogenous cells. Conidiophores reduced to conidiogenous cells. Conidiogenous cells enteroblastic, phialidic, determinate, discrete, subcylindrical to truncate, smooth-walled, hyaline, arising from the inner layers of conidiomata. Conidia fusiform, truncate at both ends, aseptate, hyaline, smooth.
Type species – Angulariaxanthoceratis R. Xu, Phukhams. & Y. Li.
Notes – Angularia is introduced for a strongly supported lineage comprising Angularia xanthoceratis (1.00 BPP, Figure 2). Angularia formed a distinct lineage to Alternariaster, Ochraceocephala, Plenodomus, Praeclarispora and Sphaerellopsis based on multi-loci phylogenetic analyses. For individual loci, Angularia formed a sister clade distinct from Heterosporicola (ITS) and a sister clade distinct from Pseudoleptosphaeria etheridgei (LSU). Leptosphaeriaceae species are remarkable for having superficial to semi-immersed, shiny ascomata or conidiomata, with thick multi layers of scleroplectenchymatous or pseudoparenchymatous tissue types [4]. The fungus has semi-immersed to immersed conidiomata, black, with multilayer scleroplectenchymatous-type tissue (Figure 3). Angularia is similar to Plenodomus and Alternariaster in having peridium with scleroplectenchymatous cells [4]. Angularia is also similar to Plenodomus and Sphaerellopsis in having textura angularis cells in the conidiomatal wall [4,24]. However, Angularia and Ochraceocephala differ substantially in morphology. Ochraceocephala has long and branched conidiophores, and the branching is commonly irregularly verticillate, while the conidiophores of Angularia are reduced to conidiogenous cells. Ochraceocephala has hyaline to yellowish, mostly sand to olive yellow, and mostly globose to subglobose conidia, while Angularia has hyaline and fusiform conidia; the conidia are smaller than in our new genus (4.8 vs. 18.7 × 3.6 vs. 5.4 μm).
Genera