Pyrenula yunguiensis M. Z. Dou & Z. F. Jia, 2024

Dou, Mingzhu, Li, Jiechen, Hu, Yongshun, Aptroot, André & Jia, Zefeng, 2024, Phylogenetic analysis shows that Pyrenula (Pyrenulaceae) diversity is larger than expected: three new species and one new record discovered in China, MycoKeys 110, pp. 159-183 : 159-183

Pyrenula yunguiensis M. Z. Dou & Z. F. Jia sp. nov.

Fig. 3

Etymology.

The specific epithet yunguiensis refers to the place where the specimen was collected.

Holotype.

China • Guizhou Province, Duyun City, Doupeng Mountain Reserve, Mayao River Street , 26°22'32"N, 107°22'11"E, alt. 1107 m, on bark, 17 March 2018, F. Y. Liu ( LCUF GZ 18096 , holotype; GenBank PP 692374 for ITS, and PP 692478 for nuLSU).

Diagnosis.

The new species can be distinguished from the most similar species P. submacularis by bigger ascospores and different lichen substances.

Description.

Thallus corticolous, crustose, olive-green in the field and khaki after drying, surface dull, corticate with pseudocyphellae, UV-. Apothecia emergent, dispersed, low conical, 0.5–2.0 mm diam., the sides often partly covered by the thallus, with crystals. Excipulum carbonized when mature and falls apart when over-mature. Ostioles apical, white. Hamathecium not inspersed, IKI + red and occasional blue, the colour relating to development stage. Ascospores 8 per ascus, uniseriate, fusiform, with pointed or blunt ends, 50–70 (– 80) × 17–22 (– 26) μm, hyaline to brown, muriform, with c. 8 × 2–4 locules, lumina rounded, old spores containing globules of red oily substance.

Chemistry.

Thallus UV-. TLC with solvent C showed unidentified black spots at Rf four and six under 254 nm ultraviolet light; unidentified green spot at Rf four on charred plate under daylight; unidentified red spots at Rf three, four and five on charred plate under 365 nm ultraviolet light (Suppl. material 3).

Habitat and distribution.

The new species is currently only known from the subtropical regions of southern China on bark.

Additional specimens examined.

China • Guizhou Province, Duyun City, Doupeng Mountain Reserve, Old Post Street , 26°22'35"N, 107°21'52"E, alt. 1154 m, on bark, 17 March 2018, X. H. Wu ( LCUF GZ 18128 ; GenBank PP 692373 for ITS and PP 692479 for nuLSU) . China • Yunnan Province, Jingdong County, Taizhong Town, Aishanting , 24°32'11"N, 101°01'53"E, alt. 2625 m, on bark, 16 August 2022, T. Jia ( LCUF YN 221461 ; GenBank PP 692378 for ITS, and PP 692477 for nuLSU) .

Notes.

This new species is similar to Pyrenula seminuda , P. endocrocea , P. breutelii , P. macularis and P. submacularis in having (sub) muriform ascospores with red or orange oil when over-mature. This new species differs from P. seminuda by bigger and muriform ascospores with more locules, the latter 22–40 × 10–17 μm and submuriform with 6 × 1–2 locules, most transverse locules being single and few with an oblique or longitudinal division ( Aptroot et al. 2013). P. endocrocea differs from this new species by medulla with a soft layer of copious orange anthraquinone crystals reacting UV + red and KOH + crimson, and smaller ascospores, (30 –) 32–44 (– 50) × 13–16 (– 19) μm ( Aptroot et al. 2012). This new species differs from P. breutelii by bigger ascospores, the latter 25–35 × 12–13 μm ( Müller 1885). This new species can be distinguished from P. macularis by bigger ascospores, the latter 34–45 × 14–16 μm and 8 × 1–3 locules ( Zahlbruckner 1930). This new species can be distinguished from the most similar species P. submacularis by different lichen substances, bigger ascospores and less locules, the latter 40–65 × 16–21 (– 28) μm and 7–9 × 2–7 locules. P. submacularis (no. nr. 5 and nr. 6 in Suppl. material 3; no. nr. 8 and nr. 10 in Suppl. material 4) has one more spot with fluorescence at Rf five after charring under 365 nm ultraviolet light than P. yunguiensis (no. nr. 8 and nr. 11 in Suppl. material 3; no. nr. 12 and nr. 14 in Suppl. material 4). Although P. yunguiensis clustered with P. pyrenuloides with high support (0.99 / -), they can be distinguished easily in anatomical characters. P. pyrenuloides has no red or orange oil in over-mature ascospores and more locules (8–10 rows of up to ca. 10 each) ( Harris 1989).

Figures

Figure 3. Pyrenula yunguiensis sp. nov. (holotype, LCUF GZ 18096) A thallus with ascomata and pseudocyphellae B ascus, with 8 ascospores C – G ascospores at different developmental stages E, F over-mature ascospores with red-oil F, G red arrows show gelatinous halo. Scale bars: 1 mm (A); 50 µm (B – D); 20 µm (E, F); 40 µm (G).