Nemania hyrcana Pourmoghaddam, Voglmayr & Khodaparast, 2022

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 hyrcana Pourmoghaddam, Voglmayr & Khodaparast sp. nov.

Figs 2 , 3

Holotype.

Iran, Guilan Province, Astara County, Darband Forest, 38°21'26"N, 48°50'19"E, 17 m elev., on fallen branch of Parrotia persica , 7 October 2017, leg. M.J. Pourmoghaddam (GUM 1628; living culture MUCL 57704).

Etymology.

The epithet is derived from “Hyrcania”, an ancient biogeographical region, located in the south of the Caspian Sea where the specimens were collected.

Diagnosis.

differs from Nemania subaenea by its smaller ascospores [12-16 × 4.5-6 vs. 14-17.5 × 6-7.5 µm].

Teleomorph.

Stromata superficial, effused-pulvinate, up to 2.5 cm long, 0.2-1.4 cm wide, sessile, attachment to substrate with narrow connective; surface brown, dark brown, dark grey with a slightly shiny metallic tone, with conspicuous perithecial mounds; carbonaceous tissue immediately beneath the surface and between the perithecia; tissue beneath the perithecial layer conspicuous. Perithecia obovoid to spherical, 0.5-0.7 mm high × 0.4-0.6 mm wide; ostioles papillate to coarsely papillate. Asci cylindrical, with amyloid, urn-shaped apical apparatus, 3.5-4 µm high × 2.5-3 µm wide, stipe up to 130 µm long, spore-bearing part 60-85 × 8-12 µm. Ascospores smooth, unicellular, pale brown to brown, ellipsoid, inequilateral, with narrowly rounded ends, 12-16 × 4.5-6 µm, with straight germ slit much less than spore-length on dorsal side; perispore indehiscent in 10% KOH.

Cultures and anamorph.

Colonies on OA covering a 9 cm Petri dish in 2 wk, at first white, becoming buff (45), felty, azonate; finally, attaining cream to grey after 50 days. Anamorph geniculosporium-like. Conidiophores variables in length, hyaline to light brown. Conidiogenous cells up to 50 × 2.5-3.5 µm, hyaline to light brown. Conidia hyaline, ellipsoid with truncate base, 3.5-6 × 2.5-3.5 µm (Fig. 3 ).

Other specimen examined.

Iran, Golestan Province, Aliabad-e-Katul County, Kaboudwall Forest, 36°52'25"N, 54°53'14"E, 1076 m elev., on dead branches (host unknown), 10 November 2017, leg. M.J. Pourmoghaddam (GUM 1627; living culture MUCL 57703, IRAN 3734C).

Notes.

This species resembles Nemania subaenea (Fig. 4 ), which was erected based on a single specimen from Guyana by Ju and Rogers (2002). Later, Fournier et al. (2018) reported it from Martinique and also mentioned N. plumbea , another single-specimen-based species from Thailand ( Tang et al. 2007), which differs from N. subaenea only in the stromatal surface colour and in having slightly smaller ascospores ( Tang et al. 2007). However, neither Ju and Rogers (2002) nor Fournier et al. (2018), who proposed that N. plumbea should be regarded as a synonym of N. subaenea , studied the cultures and anamorph of the neotropical species. The type of N. plumbea , on the other hand, was cultured and DNA sequences are available for comparison with the Iranian species. A comparison of these sequence data revealed significant differences between the two Iranian strains of N. hyrcana (MUCL 57703/ MUCL 57704) and the ex-type strain of N. plumbea (29/31 bp differences of 494 nucleotide characters in the ITS: 19/20 substitutions, 10/11 indels; 2 bp differences of 764 nucleotide characters in the LSU: 2 substitutions; 27 bp differences of 884 nucleotide characters in the RPB2: 28/27 substitutions; and 319/321 bp differences of 1422 nucleotide characters in the TUB2: 279/282 substitutions, 40/39 indels). This supports the erection of a new species for the Iranian fungus, for which multiple specimens and two cultures are available. Even if N. plumbea is not regarded as a synonym of N. subaenea , it should be kept in mind that both taxa are derived from tropical areas that are far away from Iran.

Figures

Figure 2. Nemania hyrcana (Holotype GUM 1628) A, B close-up view of stromatal surface C close-up view of stromatal surface showing ostioles D, E stroma in horizontal section showing perithecia F mature ascus in water with long stipe G immature ascus in water H mature ascus in water I mature ascus in Melzer's reagent J immature and mature ascospores in water K-M ascospores in water showing straight germ slit much less than spore-length. Scale bars: 2 mm (A); 0.8 mm (B); 0.5 mm (C, E); 0.4 mm (D); 20 µm (F-I); 10 µm (J-M).

Figure 3. Culture and anamorphic structures of Nemania hyrcana (MUCL 57704) on OA A, B surface of colony after (A) 7 and (B) 50 days of incubation C conidia D-F general view of anamorph structure, conidiophores, conidiogenous cells and mature conidia of N. hyrcana. Scale bars: 10 µm (C); 20 µm (D-F).

Figure 4. Nemania subaenea (isotype) A herbarium label B close-up view of stromatal surface C close-up view of stromatal surface showing ostioles D, E stroma in horizontal section showing perithecia F immature ascus in water G ascus apical plug in Melzer's reagent H immature and mature ascospores in water I ascospore in water showing straight germ slit much less than spore-length. Scale bars: 2 mm (B); 0.8 mm (C); 1 mm (D); 0.5 mm (E); 20 µm (F); 10 µm (G-I).