Pleosporales » Phaeosphaeriaceae » Phaeosphaeriopsis

Phaeosphaeriopsis pseudoagavacearum

Phaeosphaeriopsis pseudoagavacearum Crous & Y. Marín, in Marin-Felix et al., Stud. Mycol. 94: 63 (2019)

Index Fungorum number: IF829645; Facesofungi number: FoF 07196

Holotype: FRANCE, Domaine la Fraysse, Valgorge, on leaves of Agave sp. (Asparagaceae), 15 July 2010, P.W. Crous, CBS H-23873, ex-type living culture, CBS 145370 = CPC 18383.

Saprobic on dead leaves of Yucca gloriosa. Sexual morph: Ascomata 180–260 μm high, 190–330 μm diam., scattered to clustered, gregarious, immersed, slightly raised to erumpent, visible as black dots on the host surface, globose to subglobose, uni- to bi-loculate, glabrous, ostiole central, with minute papilla. Peridium 15–60 μm wide, thin-walled of unequal thickness, composed of several cell layers, of flattened to broad, pseudoparenchymatous cells, brown to dark brown of textura angularis; thick at the apex (40–60 μm wide), arranged in a textura prismatica. Hamathecium composed of numerous, 1–1.7 μm wide, filamentous, septate, anastomosed pseudoparaphyses, embedded in a hyaline gelatinous matrix. Asci (85–)90–110(–119) × (9–)10–12(–14) μm (x̄ = 99.6 × 11.4 μm, n = 30), 8-spored, bitunicate, fissitunicate, cylindrical to subcylindric-clavate, subsessile to short pedicellate, blunt to rounded apex, with well-developed ocular chamber. Ascospores (18–)20–23(–2 5) × (4.5–)5–6.5 μm (x̄ = 21.8 × 5.6 μm, n = 30), overlapping 1–2-seriate, brown to dark brown, oblong to subcylindrical, slightly narrower towards the lower cells, 5-septate, not constricted at the septa, enlarged at the 4th cell from above, verruculose, surrounded by a distinct mucilaginous sheath. Asexual morph: Undetermined.

Material examined: ITALY, Province of Arezzo [AR], near Stia, on dead land leaves of Yucca gloriosa L. (Asparagaceae), 1 November 2016, E. Camporesi, IT3148 (MFLU 17–2800).

Known host and distribution: Agave sp. (France), Yucca gloriosa (Italy) (Marin-Felix et al. 2019; this study).

GenBank Numbers: ITS: MN750613; LSU: MN750592; SSU: MN750607; TEF1-α: MN756837 (MFLU 17–2800A); ITS: MN750614; LSU: MN750593; SSU: MN750608; TEF1-α: MN756838 (MFLU 17–2800B).

Note: Based on the NCBI BLASTn search of ITS sequence data, our newly generated sequences (MFLU 17–2800A and MFLU 17–2800B) have a 99.62% similarity with Phaeosphaeriopsis pseudoagavacearum (strain CBS 145370, GenBank no. MK539962), 98.62% similarity with P. obtusispora (Speg.) M.P.S. Câmara (strain CBS 246.64; GenBank no. KY090644) and a 98.04% similarity with P. agavacearum Crous & Thangavel (strain CPC 29122; GenBank no. NR_155689 and KY173430). Our collection morphologically resembles P. obtusispora and P. agavacearum in having 5-septate ascospores, enlarged at the 4th cell and verruculose in P. agavacearum. However, our collection can be distinguished from these two species based on the size range of ascomata, asci and ascospores as well as the host occurrences. Phylogenetic analyses of a combined LSU, SSU, ITS and TEF1-α sequence dataset showed that our strains clade with P. pseudoagavacearum (93% ML, 0.99 BYPP) and also cluster with P. agavacearum, P. obtusispora and P. grevilleae. We, therefore, identify our collection as P. pseudoagavacearum. However, the morphological characteristics of our collection could not be compared with the type of P. pseudoagavacearum as the type is represented by its asexual morph. Thus, we report the sexual morph of P. pseudoagavacearum collected from Yucca gloriosa in Italy for the first time.