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

Fig. 2

Etymology.

The specific epithet submacularis refers to the similarity to Pyrenula macularis.

Holotype.

China • Fujian Province, Wuyi Mountain, Tongmu Village Reserve, Wuyi Mountain National Park , Science and Technology Building , 27°44'31"N, 117°40'44"E, alt. 700 m, on bark, 24 October 2021, Y. F. Zhao ( LCUF FJ 211750 , holotype; GenBank PP 692372 for ITS, and PP 692480 for nuLSU).

Diagnosis.

The new species can be distinguished from the most similar species Pyrenula macularis Aptroot by bigger ascospores with more locules 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, 1.0–2.0 mm diam., the sides often partly covered by the thallus, with crystals, wall completely carbonized when mature and even falls apart. Ostioles apical, white. Hamathecium not inspersed, IKI + blue and occasionally red. Ascospores 8 per ascus, uniseriate or subbiseriate, elliptical, with rounded ends, 40–65 × 16–21 (– 28) μm, hyaline to brown, muriform, with c. 7–9 × 2–7 locules, lumina rounded, old spores containing globules of red oily substance.

Chemistry.

Thallus UV-. TLC with solvent C showed unidentified black spots at Rf two, three, four, five and six under 254 nm ultraviolet light; unidentified green spot at Rf four and brick red spots at Rf five after charring under daylight; unidentified red spots at Rf three and four, and one unidentified fluorescent spot at Rf five after charring 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 • Fujian Province, Longyan City, Dongxiao National Forest Park, Frog Stone , 24°58'07"N, 117°01'14"E, alt. 679 m, on bark, 12 July 2022, Z. G. Ma ( LCUF FJ 220211 ; GenBank PP 692377 for ITS, and PP 692481 for nuLSU) .

Notes.

This new species is similar to Pyrenula seminuda , P. endocrocea , P. breutelii and P. macularis 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 ( P. submacularis ) differs from P. breutelii in lichen substances (Suppl. material 3) and by bigger ascospores and more locules, the latter 25–35 × 12–13 μm and 8 × 3–4 locules ( Müller 1885). P. submacularis (no. nr. 5 and nr. 6 in Suppl. material 3) has two more black spots at Rf two and three under 254 nm ultraviolet light than P. breutelii (no. nr. 15 and nr. 16 in Suppl. material 3). And the new species has one more spot with fluorescence at Rf five after charring under 365 nm ultraviolet light than P. breutelii (Suppl. materials 3, 4). This new species ( P. submacularis ) can be distinguished from the most similar species P. macularis by different lichen substances and bigger ascospores and more locules, the latter 34–45 × 14–16 μm and 8 × 1–3 locules ( Zahlbruckner 1930). P. macularis (no. nr. 5 and nr. 6 in Suppl. material 4) has two more black spots at Rf two under 254 nm ultraviolet light than P. submacularis (no. nr. 8 and nr. 10 in Suppl. material 4). And the new species has one more spot with fluorescence at Rf five after charring under 365 nm ultraviolet light than P. macularis (Suppl. materials 3, 4).

Figures

Figure 2. Pyrenula submacularis sp. nov. (holotype, LCUF FJ 211750) A thallus with ascomata and pseudocyphellae B ascospores at different developmental stages C ascus, with 8 ascospores D red arrows show gelatinous halo E, F over-mature ascospores with orange-oil. Scale bars: 1 mm (A); 30 µm (B); 20 µm (C, D); 10 µm (E, F).