Myriolecis mons-nivis (Darb.) Śliwa, Zhao Xin & Lumbsch.

Fig. 6

Description.

Thallus clearly visible, thin, continuous, more or less rimose, edge indefinite, brown to dark brown; prothallus not seen; Apothecia numerous, usually clustered in groups or occurring singly, sessile or constricted at the base, 0.3–0.8 mm in diameter; Disc plane smooth, dark brown to dark blue, epruinose; thalline margin level with the disc, rough, cracked with numerous small fissures or flexuose or incised, epruinose, white to grayish-white; Amphithecium not well delimited into algal layer and cortex, algal layer with algae abundant filling, continuous; cortex indistinctly divided, composed of granules (pol +, insoluble in K and N); Epithecium shades of reddish-brown to brown, granules superficial and inspersed in paraphyses tips (pol ±, insoluble in K and N); Hymenium hyaline, 45–65 μm high; Subhymenium indistinct or distinct, thin, hyaline; Hypothecium hyaline 40–65 μm high, composed of gelatinized hyphae (most clear in K); Paraphyses slender, simple, never branched, expanded to capitate apically, red-brownish pigmented, with sharply delimited as a cap (up to 0.3 μm), coherent in K. Asci clavate, 8 - spored; Ascospores hyaline, simple, broadly ellipsoid to narrowly ellipsoid, 7–12 × 5–8 μm, Pycnidia not seen.

Chemistry.

Apothecial margin K –, C –, KC –, PD –; disc K –, C –, KC –, PD –; No lichen products detected by TLC.

Habitat.

On calcareous rock.

Notes.

The species can be easily identified by its clearly visible, rimose thallus and dark brown, usually epruinose apothecial disc, as well as by its white to ash-gray apothecial margin with slight cracks and reddish-pigmented epithecium. This species is closely related to M. flowersiana, which differs in its apothecial color and has more submoniliform, pigmented, and distinctly septate paraphyses as well as narrowly ellipsoid spores. Additionally, the epithecium of M. flowersiana is deeply pigmented, with up to one-third of the upper hymenium exhibiting more intense red coloration (Śliwa 2007; De la Rosa et al. 2012). Morphologically, the newly recorded species is identical to M. dispersa (Pers.) Śliwa, Zhao Xin & Lumbsch; however, M. dispersa has an inconspicuous thallus and a distinctly granular epithecium that is tinged yellow or brown, contains pannarin, and has a PD + orange reaction of the apothecial margin (Fröberg 1997; Śliwa 2007; Muchnik and Śliwa 2011; De la Rosa et al. 2012).

Specimens examined.

China • Xinjiang, Atux, Aketao County, Oytag, Mt. Southern Tianshan, 38°53'54"N, 75°11'57"E, 2930 m a. s. l., on rock, 27 Aug 2013, R. Mamut 201367, 201368, 201366, 201369, 201364, 201363 (XJU).