Atrocalyx A. Hashim. & Kaz. Tanaka, Persoonia 39: 59 (2017).
Index Fungorum number: IF 819240; Facesoffungi number: FoF 08286, 7 morphological species (Species Fungorum, 2022), 7 species with molecular data.
Saprobic on woody plants. Sexual morph: Ascomata solitary to grouped, semi-immersed to immersed. Ostiolar neck crest-like, elongated and laterally compressed, surrounded by dark brown hyphae. Peridium composed of 2 zones at side. Pseudoparaphyses septate, branched and anastomosed. Asci bitunicate, fissitunicate, cylindrical, 8-spored. Ascospores broadly fusiform, hyaline, 1-septate, smooth. Asexual morph: Conidiomata pycnidial, globose to subglobose, superficial, black, ostiolate. Peridium composed of elongated, brown cells. Conidiophores absent. Conidiogenous cells holoblastic, ampliform to cylindrical, hyaline. Conidia ellipsoidal, hyaline, smooth, aseptate (adapted from Hashimoto et al. 2017).
Type species: Atrocalyx acutispora A. Hashim. & Kaz. Tanaka
Notes: Atrocalyx was introduced by Hashimoto and Tanaka (2017) with A. acutispora as type species. Atrocalyx is characterized by solitary to grouped, semi-immersed ascomata, crest-like, elongated ostiolar neck, fissitunicate, cylindrical, 8-spored asci and broadly fusiform, hyaline, 1-septate ascospores. The asexual morph is characterized by pycnidial, globose to subglobose conidiomata, holoblastic, ampliform to cylindrical, hyaline conidiogenous cells and ellipsoidal, hyaline, smooth, aseptate conidia. Atrocalyx is morphologically similar to Lophiotrema but can be differentiated in having a well-developed peridium around the ostiolar neck and base. Several authors added new species to Atrocalyx (Tibpromma et al., 2017; De Silva et al., 2018; Jaklitsch et al., 2018; Jayasiri et al., 2019). Atrocalyx is morphologically and phylogenetically a well-defined genus in Lophiotremataceae. Molecular markers available for Atrocalyx are LSU, SSU, ITS, TEF1.