Hydeomyces Maharachch., Ariyawansa, Wanas. & Al-Sadi, 2019

Maharachchikumbura, Sajeewa S. N., Ariyawansa, Hiran A., Wanasinghe, Dhanushka N., Dayarathne, Monika C., Al-Saady, Nadiya A. & Al-Sadi, Abdullah M., 2019, Phylogenetic classification and generic delineation of Hydeomyces desertipleosporoides gen. et sp. nov., (Phaeosphaeriaceae) from Jebel Akhdar Mountain in Oman, Phytotaxa 391 (1), pp. 28-38 : 33

Hydeomyces Maharachch., Ariyawansa, Wanas. & Al-Sadi , gen. nov.

MycoBank number: MB 827328; Facesoffungi number: FoF 05381

Etymology: Named in honour of British mycologist K.D. Hyde, for his huge contribution to ascomycete taxonomy

Saprobic in terrestrial habitats. Sexual morph: Ascomata partly immersed to erumpent in woody tissue, solitary or rarely confluent, globose-depressed, brown to black; apex with a central coriaceous, papillate ostiolar perforation, without periphyses. Peridium with 2–5 layers, comprising heavily pigmented, thin-walled, brown to dark brown cells of textura angularis-globosa. Hamathecium comprising filamentous, pseudoparaphyses. Asci 8-spored, bitunicate, fissitunicate, cylindrical, with a minute ocular chamber. Ascospores sometimes partially overlapping or obliquely uniseriate, ellipsoidal to subfusiform, muriform, upper part wider than the lower part, lacking mucilaginous sheath. Asexual morph: Pycnidia initially hyaline transparent or brown becoming dark brown with age, globose, glabrous with a narrow ostiolum. Conidia hyaline, smooth-walled, produced on short phialides lining the pycnidial cavity.

Type: Hydeomyces desertipleosporoides Maharachch., Ariyawansa, Wanas. & Al-Sadi

Notes: Two strains of sexual morph (SQUCC 15259, SQUCC 15260) clustered in the Phaeosphaeriaceae as a strongly supported monophyletic clade ( FIGURE 1 ) in both ML and BI analyses. Both specimens were collected from Al Jabal al-Akhdar (Green Mountain), from dead bark of Juniperus excels , but in different seasons as July 2016 (SQUCC 15259) and April 2017 (SQUCC 15260) respectively. Since taxa collected herein clearly form an independent lineage and are phylogenetically segregated from other genera, we introduce, Hydeomyces , a new genus to accommodate these isolates with illustrated phenotypic data ( FIGURE 2 ). Hydeomyces is morphologically similar to Allophaeosphaeria , Dactylidina , Dematiopleospora , Dlhawksworthia , Embarria , Italica , Muriphaeosphaeria , Poaceicola and Populocrescentia in having muriform ascospores in Phaeosphaeriaceae . Although there is albeit morphological overlap between Hydeomyces and the above-mentioned genera, our phylogenetic results based on multi-gene phylogenetic analyses give clear cut significances for generic delineation to our taxa collected herein ( FIGURE 1 ).

Figures

FIGURE 1. Maximum likelihood (ML) tree resulting from a RAxML analysis of the combined (LSU+SSU+TEF+ITS) alignment of the analysed genera in Phaeosphaeriaceae. RAxML bootstrap support values (ML) and Bayesian posterior probabilities (BI) are given at the nodes (ML/BI). Genera are indicated in coloured blocks and newly introduced strains are in bold. The species name is followed by the strain accession numbers. The tree is rooted to Staurosphaeria rhamnicola (MFLUCC 17-0813).

FIGURE 2 Hydeomyces desertipleosporoides (SQU H-101, holotype) a Ascostromata on substrate. b, c Ascoma in vertical section. d Peridium. e Periphyses. f–j Asci k–n Ascospores. o Cultures on PDA. p Pycnidium on PDA. q–s Pycnidia. t Conidia. Scale bars b, q–s = 50 μm, b = 100 μm, e, t = 20 μm, k–n = 10 μm. Scale bar of b applies to b–c. Scale bar of e applies to e–j.