Nemania diffusa (Sowerby) S.F. Gray, Nat. Arr. Brit. Pl. (London) 1: 517 (1821).

Pourmoghaddam, Mohammad Javad, Lambert, Christopher, Voglmayr, Hermann, Khodaparast, Seyed Akbar, Krisai-Greilhuber, Irmgard & Stadler, Marc, 2022, Note on the genus Nemania (Xylariaceae) - first records and a new species of the genus from Iran, MycoKeys 93, pp. 81-105 : 81

Nemania diffusa (Sowerby) S.F. Gray, Nat. Arr. Brit. Pl. (London) 1: 517 (1821).

Fig. 8

Teleomorph.

Stromata superficial, effused-pulvinate, discoid, up to 2 cm long × 0.3-1.5 cm wide, sessile, attachment to substrate with narrow connective; surface dark brown to blackish-brown, with inconspicuous perithecial mounds, carbonaceous immediately beneath surface; tissue between and beneath perithecia black to dark brown. Perithecia obovoid to cylindrical, 0.5-0.8 mm high × 0.3-0.5 mm wide. Ostioles papillate to coarsely papillate. Asci cylindrical, with amyloid, urn-shaped apical apparatus, 2-3 µm high × 1.5-2 µm wide, stipe up to 100 µm long, spore-bearing part 70-80 × 7-10 µm. Ascospores smooth, unicellular, brown to dark brown, ellipsoid, inequilateral, with narrowly rounded ends, 9.5-13(-14) × 4.5-6.5 µm, with straight germ slit spore-length on flattened side; perispore indehiscent in 10% KOH.

Specimen examined.

Iran, Guilan Province, Rezvanshahr County, 37°37'52"N, 40°02'18"E, 7 m elev., on fallen branch of Quercus castaneifolia , 6 October 2016, leg. M.J. Pourmoghaddam (GUM 1626), ITS and LSU sequences GenBank OP352258 and OP352270, respectively.

Notes.

Nemania diffusa , originally described from England ( Sowerby 1803), is a widespread and fairly common species in Europe ( Fournier et al. 2018). It has also been reported from North and South America ( Petrini and Rogers 1986), Papua-New Guinea (Van der Gucht 1995) and Taiwan (Ju and Rogers 1999), but it has yet to be proven whether all these morphologically identified accessions are conspecific with the European ones. The Iranian specimen is in accordance with previous descriptions by Ju and Rogers (2002). It can be differentiated from N. albocincta by its larger ascospores [9.5-13.5 × (4.5-)5-6 vs. 8-10 × 4-5 µm], which are also more equilateral. Nemania obscura also differs from it in stromatal features and smaller, strongly inequilateral ascospores (8.2-9.4 × 4.5-5.3 µm) with subacute ends. Despite several attempts, we could not achieve a living culture. Therefore, to confirm our morphological species identification, we extracted DNA from stromata and performed PCR (ITS/LSU) and sequencing according to Pourmoghaddam et al. (2018). The ITS sequence of the Iranian collection (OP352258) is completely identical to numerous sequences of European accessions of N. diffusa , some of which are morphologically well-documented to represent the species (e.g. MW489542 from Switzerland; Senn-Irlet et al. 2021), confirming the species identification. However, as RPB2 and TUB2 could not be obtained, the Iranian accession of N. diffusa was not added to the phylogenetic multi-locus analyses.

Figures

Figure 8. Nemania diffusa (GUM 1626) A stromatal habit B close-up view of stromatal surface C, D close-up view of stroma surface showing ostioles E mature ascus in water F, G mature asci in Melzer's reagent showing the amyloid (bluing) ascal apical apparatus H ascospore showing straight germ slit. Scale bars: 3 mm (B); 1.5 mm (C); 0.8 mm (D); 20 µm (E-G); 10 µm (H).