Pertusaria tibetensis Z.S. Sun, 2018

Sun, Zhong-Shuai & Zhao, Zun-Tian, 2018, A new species of Pertusaria (Pertusariaceae, Ascomycota) from Qinghai-Tibet Plateau of China, Phytotaxa 333 (1), pp. 143-146 : 144-145

Pertusaria tibetensis Z.S. Sun , sp. nov.

MycoBank No.: MB 821796

Similar to Pertusaria submultipuncta Nyl. , but differs in having pinkish discs and a smooth unzoned spore wall and slightly smaller ascospores.

Type:— CHINA. Tibet: Linzhi County, Lulang Town, Shergyla National Forest Park ; 29°36′11″N, 94°36′21″E, alt. 4120 m; on living treetrunk; 26 October 2007, G. Y. Han 20073197 (holotype in SDNU) .

Etymology: The specific epithet tibetensis is derived from the type locality in Tibet, CHINA.

Thallus crustose, thin, corticolous; upper surface gray to grayish-white, rough, tuberculate; soredia and isidia absent. Fertile verrucae lecanorate, concolorous with thallus, constricted at the base, well dispersed or locally crowded and rarely fused, 0.5–1.0 mm in diam.. Discs pink, level or usually deeply sunken, white-pruinose, the verrucal margins thick, initially entire and later ruptured forming a false secondary edge to the verrucae. Apothecia 1- (2-3) per verruca, the fruit centre hyaline. Epithecium red-brown, K–. Ascospores 1 per ascus, ellipsoid to cylindric, 100–110 μm long, 40–50 μm wide, spore wall smooth, unzoned. Pycnidia not seen.

Chemistry: K+ red, C–, KC–, Pd+ yellow, UV–; norstictic acid (TLC).

Ecology and distribution: —At present, Pertusaria tibetensis is known only from the type locality; on Abies or Rhododendron .

Discussion:— Pertusaria tibetensis is characterised by broad lecanorate verrucae, pinkish pruinose discs, 1- spored asci and containing norstictic acid. The most similar species is Pertusaria submultipuncta Nyl. , which also has lecanorate verrucae and contain norstictic acid, but differs by disc colour and double-walled spores ( Oshio 1968, Zhao et al. 2004). The new species is distinguished from P. sanguinolenta Zahlbr. ( Zahlbruckner 1930) by the epruinose discs and the larger ascospores, 140–160 μm long, present in P. sanguinolenta . The new species also resembles Pertusaria wangii Q. Ren , a species distributed in southwestern China, but the latter has 8-spored asci and the thicker thallus ( Ren & Zhao 2014).

Additional material examined: — CHINA. Tibet: Linzhi County, Lulang Town, Shergyla National Forest Park, east slope of Mt. Shergyla ; 29°36′11″N, 94°36′21″E, alt. 4110-4200 m, 26 October 2007, G. Y. Han, 20073164 ; 20073198; 29°36′33″N, 94°35′50″E, alt. 4200m- 4400m, 27 October 2007, G. Y. Han, 20073299 ; 20073353 (SDNU).