Ochrolechia subrosella Z. F. Jia & Z. T. Zhao

Ochrolechia subrosella Z. F. Jia & Z. T. Zhao View in CoL

Fig. 6 View Figure 6

Remark.

Mycosystema 24 (2): 162 (2005); type: China, Yunnan, Dali , Wei WY 014-1 ( HMAS-L – holotype) .

Description.

Thallus greyish-brown, thick, cracked, verruculose to verrucose, dull; prothallus indistinct; isidia and soredia absent.

Sexual morph. Apothecia frequent, scattered, sessile and round, becoming remarkably large at maturity ( 2.5–4 mm in diameter) and covered with white pruina Disc pale pink, plane when young, rough to rugose at maturity, followed by a radial bulge; margins thick and smooth when young, becoming thin and verrucose when older, slightly lighter in colour than disc. Pycnidia are absent. Hymenium hyaline, 290–340 μm high; epihymenium brown (the colour partially or completely disappears in a 10 % KOH solution), 20–25 μm high; hypothecium 20–30 μm high; coccoid green alga, algae forming a continuous layer in the margin and below the hypothecium. Asci narrowly clavate, 8 - spored, (210) 218–243 (250) × (51) 56–67 (70) μm (n = 11). Ascospores hyaline, aseptate, ellipsoid to broadly ellipsoid, (50) 54–64 (67) × (22) 25–31 (33) μm (n = 30).

Chemistry.

Thallus and ascomata contain gyrophoric acid and lecanoric acid ( TLC). Thallus cortex: K –, C + red, KC + red; medulla: C –; apothecia cortex: K + yellow-green, C + red, KC + red to yellow-green; medulla: C –; disc: C + red; thallus UV –.

Material examined.

China • Guizhou Province, Qiandongnan Prefecture City, Leigongshan National Nature Reserve , 26°22'41.82"N, 108°11'43.23"E, 1670 m elev., on bark, 27 October, 2023, Bo Liu and Ze Yang, LGS- 176 ( KUN-L 96624 ) GoogleMaps .

Notes.

This study provides the first DNA sequences for Ochrolechia subrosella . Phylogenetic analysis shows that this species is closely related to O. akagiensis and O. leigongshanensis , but forms a distinct, weakly-supported clade. Sequence comparison reveals that O. subrosella (LGS 176) differs from O. akagiensis (Hara Kojiro: 0007) by 6.93 % (37 / 534 bp) in ITS and from O. leigongshanensis (LGS 186) by 8.49 % (41 / 483 bp) in ITS and 1.45 % (10 / 688 bp) in mtSSU.

Morphologically, this species is characterised by mature apothecia with expanded discs bearing striated protuberances and conspicuous radial ridges, consistent with the original description of O. subrosella ( Jia and Zhao 2005) . Chemically, TLC confirmed the presence of gyrophoric acid and lecanoric acid in LGS 176, matching the secondary metabolite profile reported for O. subrosella .