Three new species of Herpothallon (Lichenized Ascomycota) from Southern China Author Liu, Linlin 0000-0003-3571-7119 Institute of Environment and Ecology, Shandong Normal University, Jinan, 250014, P. R. China. & 2743868377 @ qq. com; https: // orcid. org / 0000 - 0003 - 3571 - 7119 2743868377@qq.com Author Zuo, Qijia 0000-0001-8910-1809 Institute of Environment and Ecology, Shandong Normal University, Jinan, 250014, P. R. China. & 2020021118 @ stu. sdnu. edu. cn; https: // orcid. org / 0000 - 0001 - 8910 - 1809 2020021118@stu.sdnu.edu.cn Author Xue, Junxia 0000-0002-6387-0148 Institute of Environment and Ecology, Shandong Normal University, Jinan, 250014, P. R. China. & 2742240073 @ qq. com; https: // orcid. org / 0000 - 0002 - 6387 - 0148 2742240073@qq.com Author Ren, Zhaojie 0000-0003-3206-1484 Shandong Museum, Jinan, 250014, P. R. China. & renzhaojie 84 @ 163. com; https: // orcid. org / 0000 - 0003 - 3206 - 1484 Author Zhang, Lulu 0000-0001-8011-4451 Institute of Environment and Ecology, Shandong Normal University, Jinan, 250014, P. R. China. & 612038 @ sdnu. edu. cn; https: // orcid. org / 0000 - 0001 - 8011 - 4451 612038@sdnu.edu.cn text Phytotaxa 2023 2023-05-17 597 4 287 296 http://dx.doi.org/10.11646/phytotaxa.597.4.4 journal article 10.11646/phytotaxa.597.4.4 5d95fc7b-5173-41c3-be8f-51fe7be6c7b6 1179-3163 7958676 Herpothallon lilacinum L.L. Liu & Lu L. Zhang , sp. nov. Mycobank number: 845790 ( Figs 3 , 4 ) Type :— CHINA . Guizhou Province : Tongren City , Yang Jia Ao township , Bi Er Tang village . 874 m elev., 27°52’27.59” N , 107°58’10.71” E , on rock, 10 June 2022 , L.L. Liu , Y.X. Bi , Z.H. Jiang & D.C. Yan 20220232 ( Holotype in SDNU ) . Thallus corticolous or saxicolous, up to 3.5 cm across, irregular shaped, sometimes flaking off, loosely appressed to the substrate, rather soft, felty, often seemingly farinose, dull, white to cream white, in section up to 200 µm thick, with many calcium oxalate crystals throughout the thallus (insoluble in KOH, dissolving and recrystallizing as colourless, needle-shaped crystals in 10% H 2 SO 4 ), with 1–2 µm wide hyphae. Hypothallus whitish, byssoid, composed of 1–2 µm wide hyphae. Prothallus up to 0.8 mm broad, whitish, indistinct, byssoid to cottony, composed of interwoven and radiating hyphae. Pseudisidia numerous, unbranched, soft, whitish subglobose or irregularly cushion-shaped, fluffy-felty with many projecting hyphae, basally of the same colour as the thallus, upper parts often lilac to lilac grey, 0.1–0.45 mm in diam.. Photobiont trentepohlioid, in short, irregular threads; cells yellowish green, 10–15 × 5–8 μm. Asci and pycnidia not seen. Chemistry and spot tests: Thallus and prothallus K−, C−, P+ bright yellow, UV−, I+ blue in medulla, the lilac to lilac grey parts K+ black blue, C−. TLC: psoromic acid (major), an unknown substance (minor), 2’-O-demethylpsoromic acid (minor). Etymology: The epithet “ lilacinum ” refers to the lilac to lilac grey pseudisidia. Ecology and distribution: The new species was found growing on rock wall by the roadside and bark of a tree in Guizhou Province . Notes: This species is characterized by the subglobose or irregularly cushion-shaped, lilac to lilac grey, fluffy-felty pseudisidia, 0.1–0.45 mm in diam., the psoromic and 2’-O-demethylpsoromic acids, and an unknown substance chemistry. Herpothallon lilacinum is most similar to H. weii Yuliang Chen & Haiying Wang (2012: 440) : both contain psoromic acid and the similar unknown substance, but H. weii has a tightly appressed thallus, an I− medulla, a distinct prothallus, pinkish and larger, and not whitish subglobose pseudisidia, up to 1 × 0.5 mm ( Cheng et al . 2012 ). Crypthonia albida (Fée) Frisch & G. Thor (2010: 290) also has fluffy-felty pseudisidia and contains psoromic acid as its major substance, but has loosely byssoid, whitish pseudisidia, up to 1.0 × 1.0 mm (Frisch & G. Thor, 2010). Herpothallon himalayanum Jagadeesh & Sinha (2009: 40) and H. capilliferum Pengfei Chen & Lulu Zhang (2022: 02) are also similar to H. lilacinum in producing fluffy-felty pseudisidia, but they differ in secondary chemistry: Herpothallon himalayanum contains gyrophoric acid as its major substance (Jagadeesh & Sinha, 2009), and H. capilliferum only contains norstictic acid ( Chen et al . 2022 ). FIGURE 3. A–B. Herpothallon lilacinum growing on rock, (holotype, SDNU 20220232). A. Thallus and prothallus. Scale = 1 mm.. B. Pseudisidia. Scale = 400 µm. C–D. The new species H. lilacinum growing on bark, (paratype, SDNU 20220090). C. Thallus. Scale = 1.5 mm. D. Pseudisidia. Scale = 600 µm. FIGURE 4. TLC of H. lilacinum with C system ( at : atranorin; U : the unknown substance; P : psoromic acid). Phylogenetically, H. lilacinum clusters with H. echinatum and H. glaucescens ( Fig. 1 ), they all possess psoromic acid as major, but H. echinatum and H. glaucescens have subglobose or cylindrical pseudisidia, all without the unknown substance. Additional specimen examined: CHINA . Guizhou Province : Tongren City , Yang Jia Ao township , Bi Er Tang village . 874 m elev., 27°52’27.59” N , 107°58’10.71” E , on rock, 10 June 2022 , L.L. Liu , Y.X. Bi , Z.H. Jiang & D.C. Yan 20220231, 20220237, 20220238, 20220239, 20220240, 20220253 ( SDNU ) ; Guizhou Province : Tongren City , Xu Jia Ba town , Zhang Jia Gou village , along the stream. 851 m elev., 27°55’33.38” N , 108°1’59.13” E , on bark of a tree, 11 June 2022 , L.L. Liu , Y.X. Bi , Z.H. Jiang & D.C. Yan 20220090 ( SDNU ) .