Rhamphoriales K.D. Hyde & Hongsanan, ord. nov.
MycoBank number: MB 557988; Index Fungorum number: IF 557988; Facesoffungi number: FoF 09418;
Type family: Rhamphoriaceae Réblová
Saprobic on decaying wood from freshwater or terrestrial habitats. Sexual morph: Ascomata perithecial, immersed or particularly erumpent becoming superficial, papillate or with a central cylindrical or rostrate neck. Ostiole periphysate. Peridium comprising two layers, leathery to fragile. Paraphyses cylindrical, septate. Asci 8‑spored, unitunicate, cylindrical or cylindrical‑clavate, persistent, with a J‑, apical ring. Ascospores uniseriate, overlapping, hyaline or brown, ellipsoidal, obovoid, clavate, fusiform to fusiform‑clavate, dictyoseptate or transversely septate, lacking mucilaginous sheaths or appendages, in some species ascospores may produce ascoconidia while in the asci (e.g. Rhamphoria pyriformis). Asexual morph: Hyphomycetous. Conidiophores macronematous or semi‑macronematous, mononematous or loosely fasciculate. Conidiogenous cells holoblastic, conidial secession rhexolytic on sympodially extending polyblastic conidiogenous cells, or schizolytic on monoblastic conidiog enous cells. Conidia hyaline or brown, aseptate or septate.
Notes: Rhamphoriaceae was established by Réblová et al. (2018) to accommodate three genera, Rhamphoria, Rhamphoriopsis and Rhodoveronaea, with Rhamphoria as the type. A strain of Linkosia multiseptum (HKUCC 10825) was also included in this family, as it clustered within Rhamphoriaceae. However, the placement of this strain (Linkosia multiseptum HKUCC 10825) is doubtful as the morphological characters are lacking, and also both morphology and sequence data of the holotype (WUWP WU 1374b) of this species are not available.
Previous phylogenetic analysis showed that Rhamphoria, Rhamphoriopsis and Rhodoveronaea clustered together with strong bootstrap support and shared a sister clade with Sporidesmiaceae (Réblová et al. 2018; Luo et al. 2019; Hyde et al. 2020a). Our phylogenetic analysis provided a similar result. Rhamphoriaceae is currently placed in incertae sedis within Diaporthomycetidae. Morphologically, we can distinguish Rhamphoriaceae from Sporidesmiaceae in the sexual morph, by the two‑layered peridium, hyaline or brown, ellipsoidal, obovoid, clavate, fusiform to fusiform‑clavate ascospores, lacking mucilaginous sheaths or appendages, whereas, Sporidesmiaceae has three‑layered peridium, hyaline, fusiform ascospores with a thin sheath. In the asexual morph, Rhamphoriaceae differs from Sporidesmiaceae by the conidiogenous cells (polyblastic, monoblastic, den‑ ticulate vs. monoblastic, terminal, and percurrently) and conidia (ellipsoidal to obovoid, aseptate or septate, hyaline or brown vs. obclavate, subobtuse at apex, truncate at base, transversely euseptate or distoseptate, brown) (Réblová et al. 2018; Yang et al. 2018; Luo et al. 2019; Hyde et al. 2020a). Divergence time estimates showed that the stem age of Rhamphoriaceae is 133 MYA, this falls within the range of orders (Hyde et al. 2017). Based on the phylogeny, divergence time estimates and morphological characters, we herein, introduce a new order Rhamphoriales to accommodate Rhamphoriaceae.