Buellia elegans Poelt, Nova Hedwigia 25(1-2): 184-186 (1974)

Ai, Min, Li, Li Juan, Worthy, Fiona Ruth, Yin, An Cheng, Zhong, Qiu Yi, Wang, Shi Qiong, Wang, Li Song & Wang, Xin Yu, 2022, Taxonomy of Buellia epigaea - group (Caliciales, Caliciaceae), revealing a new species and two new records from China, MycoKeys 92, pp. 45-62 : 45

Buellia elegans Poelt, Nova Hedwigia 25(1-2): 184-186 (1974)

Fig. 6

Type.

Italy. Ad terram calcaream supra Clavennam ( Madèsimo), Anzi M. (M! - Holotype) .

Description.

Thallus effigurate with distinct marginal lobes slim, 0.5-1 mm wide, the edge usually separated from the substrate and clearly foliaceous, thallus radiate, 1-2 cm in diam., prothallus absent; upper surface white, dull, usually covered with granular pruina; the upper cortex about 20 µm thick, with granular crystals, and the lower surface light brown to white, without cortex; medulla white, without calcium oxalate crystals. Apothecia sparse, lecideine; disc and margin black, sometimes lightly pruinose, roundish, 0.3-1.0 mm in diam., immersed and smooth when young but adnate and convex when mature; margin persistent; exciple thick, dispersa -type, without aeruginose pigments (HNO3-); epihymenium brown to dark brown; hymenium hyaline, 70-90 µm tall, without oil droplets, paraphyses simple to moderately branched, apically swollen, with a brown pigment cap; hypothecium dark brown; asci oval-clavate, Bacidia -type, eight-spored; spores 1-septate, hyaline when young, turning brown when mature, Buellia -type, ellipsoid, not thickening during spore ontogeny, 15-22 × 7-10 µm. Pycnidia not seen.

Chemistry.

Thallus K+ yellow, C-, KC-, PD-, UV+ yellow, medulla I-; containing atranorin and norstictic acid (trace) or atranorin and 2'-O-methylperlatolic acid.

Distribution and ecology.

This species is mainly distributed in open and dry soil or soil over rock or within meadows between elevations of 1400-4730 m. This species has been recorded in Asia, Afghanistan, Europe and North America (Thomson, 1997). In China, it is mainly distributed in Gansu, Ningxia, Qinghai, Xizang and Yunnan Provinces.

Note.

This is a new record for China, and is unique among species of Buellia due to its effigurate thallus, marginal lobes linear and slim, branched near the tips. It resembles folicolous species of Physconia Poelt, but could be differentiated by its slim lobes and lack of lower surface. It has a wide distribution across the Tibetan Plateau, especially in arid deserts and meadows. Four chemotypes of the species were previously reported ( Trinkaus and Mayrhofer 2000). Only two chemotypes have been detected in Chinese materials: atranorin and 2'-O-methylperlatolic acid account for the majority, atranorin and norstictic acid (trace) constitute only a small proportion.

Selected specimens examined.

China. Gansu Prov.: Jiayuguan Ci., Xigou, mineral, on soil, 39°39'34"N, 97°56'15"E, alt. 2198 m, 28 May 2018, L.S. Wang et al. 18-59611; Yumen Ci., meadow along the route from Yumen to Yuerhong, on soil, 39°57'45"N, 96°39'23"E, alt. 2395 m, 27 May 2018, L.S. Wang et al. 18-59513. Ningxia Prov.: Zhongwei Ci., Shanpotou, Mengjiawan, on soil, 37°36'12"N, 104°55'06"E, alt. 1403 m, 18 Sep. 2010, D.L. Niu et al. 10-0089. Qinghai Prov.: Wulan Co., desert along the route from Wulan to Delingha, on soil, 37°02'08"N, 98°12'29"E, alt. 3072 m, 20 May 2018, L.S. Wang et al. 18-58303; Dulan Co., Xiangjia Vil., on sandy rock, 36°00'53"N, 97°44'36"E, alt. 3056 m, 15 Sep. 2020, L.S. Wang et al. 20-68266. Xizang Prov.: Dazi Dis., Bangdui Vil., on soil, 29°44'06"N, 91°24'55"E, alt. 3709 m, 16 Jul. 2019, L.S. Wang et al. 19-64615; Basu Co., beside Ranwu Lake, on soil over rock, 29°23'34"N, 96°50'20"E, alt. 3901 m, 15 Jul. 2019, X.Y. Wang et al. (XY19-278; XY19-272); Geji Co., beside S301 road, on soil, 32°14'47"N, 82°10'27"E, alt. 4514 m, 21 Jul. 2019, L.S. Wang et al. 19-63808; Bomi Co., along the route to Basu Co., on soil, 29°40'31"N, 96°12'38"E, alt. 2920 m, 10 Nov. 2018, L.S. Wang et al. 18-62336; Langkazi Co., Simila Mt., on soil over rock, 28°50'37"N, 89°51'54"E, alt. 4343 m, 24 Jul. 2019, X.Y. Wang et al. XY19-1372; Sangri Co., Sangri Town, on soil over rock, 29°17'29"N, 92°05'30"E, alt. 3595 m, 30 Jul. 2019, X.Y. Wang et al. (XY19-1899; XY19-1907); Jangzi Co., Simila Mt., on soil over rock, 28°50'30"N, 89°51'48"E, alt. 4223 m, 24 Jul. 2019, X.Y. Wang et al. XY19-2308; Jiangda Co., Kakong Vil., on soil over rock, 31°20'22"N, 98°08'01"E, alt. 3785 m, 23 Sep. 2020, L.S. Wang et al. 20-68931. Yunnan Prov.: Deqin Co., Benzilan Vil., on soil over rock, 28°10'27"N, 99°22'53"E, alt. 2007 m, 26 Sep. 2020, L.S. Wang et al. 20-69241; Deqin Co., Benzilan Vil., beside JinSha river, on soil, 28°11'36"N, 99°21'08"E, alt. 2108 m, 19 Aug. 2018, L.S. Wang et al. 18-60340; Deqin Co., Benzilan Vil., on soil, 28°13'38"N, 99°19'20"E, alt. 2110 m, 3 Jul. 2012, L.S. Wang et al. 12-34754.

Figures

Figure 6. Morphology of Buellia elegans (16 - 51770 KUN) A thallus on soil within meadow B lecideine apothecia C the section of apothecium, exciple dispersa - type D ascospores with 1 - septate, Buellia - type E mature ascus containing eight spores, Bacidia - type. Scale bars: 2 mm (A); 1 mm (B); 50 µm (C); 10 µm (D, E).