Myriolecis wetmorei (Śliwa) Śliwa, Zhao Xin & Lumbsch.

Fig. 7

Description.

Thallus not clearly visible within the substratum and present only under apothecia or poorly developed; prothallus not seen; Apothecia lecanorine, sessile, constricted at the base, occurring singly and usually rarely clustered in groups, 0.4–1.0 mm diam.; disc black, strongly pruinose, never epruinose, smooth, flat; thalline margin prominent, level with the disc, smooth, thick, heavily white pruinose; Amphithecium developed with distinctly delimited into algal layer and cortex, algae abundant and dense, continuous; cortex strongly expanded at the base, 15–35 μm wide laterally and 50–65 μm wide at the base, composed of granules (pol +, insoluble in K, soluble in N); Epithecium brown to dark brown, N + reddish at beginning and then soon disappearing, granules superficial (pol +, soluble in K, insoluble in N); Hymenium hyaline, 45–65 μm high; subhymenium distinct, 25–65 μm high; Hypothecium hyaline, 35–50 μm high, composed of gelatinized hyphae. Paraphyses simple, rarely branched, expanded, pigmented, free in K. Asci clavate, 8 - spored; Ascospores hyaline, simple, ellipsoid (broadly ellipsoid to ellipsoid), 8.5–12 × 4.5–6.5 μm; Pycnidia not seen.

Chemistry.

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

Habitat.

Corticolous species occurring on tree bark.

Notes.

M. wetmorei is sometimes difficult to separate from M. hagenii and M. perpruinosa, as the three species possess finely pruinose apothecia. M. hagenii is distinguished on account of smaller apothecia (up to 0.8 mm diam.) with a much thinner, entire to incised rather than cracked apothecial margin. M. perpruinosa differs from M. wetmorei by having a clearly visible thallus and greenish cortex cell walls, with the outer part of the cortex turning purple in N (Fröberg 1997; Śliwa 2007; Muchnik and Śliwa 2011). Morphologically, the newly recorded species is identical to M. torrida (Vain.) Śliwa, Zhao Xin & Lumbsch, but the latter species is easily separable by its more warted and rimose-areolate thallus. In addition, anatomically, it differs in having its epithecium colored olive-green, intensely green with K, and turning reddish-brown or red in N (Śliwa and Olech 2002; Śliwa 2007).

Specimens examined.

China • Xinjiang, Urumqi City, Mt. Middle Tianshan, Yingxiong Bridge, 43°28'08"N, 87°05'48"E, 2110 m a. s. l., on bark, 15 Aug 2006, R. Mamut 060815 (XJU); • Aksu City, Kucha County, Mt. Southern Tianshan, Tilmat Daban, 2450 m a. s. l., on bark, 13 May 2007, R. Mamut 20121719, 2003111 (XJU); • Atux City, Aketao County, Oytag, Mt. Southern Tianshan, 2930 m a. s. l., 38°53'25"N, 75°11'57"E, on bark, 27 Aug 2013, R. Mamut 20137264 (XJU).