Ochrolechia kuankuoshuiensis Zheng & Meng, 2025

Ochrolechia kuankuoshuiensis Zheng & Meng sp. nov.

Fig. 3 View Figure 3

Remark.

Distinctive features of O. kuankuoshuiensis are the large ascospores (( 90) 97–116 (123) × (30) 33–35 (36) μm) and chemistry, which is limited to gyrophoric acid and lecanoric acid.

Type.

China • Guizhou, Zunyi City, Kuankuoshui Nat. Res , on bark, 1529 m elev., 2023, WW. Zheng and B. Liu, LGS 219 ( KUN-L 96619 , holotype) .

Etymology.

The species epithet refers to Kuankuoshui, the locality where the type species was collected.

Holotype.

KUN-L 96619 .

Description.

Thallus greyish-white, thick, scaly, dull, verruculose; prothallus indistinct; isidia and soredia absent.

Sexual morph. Apothecia frequent, mostly scattered, sometimes crowded, sessile, irregularly rounded or irregularly florid, 0.5–2.5 mm diam.; disc light yellow, epruinose, rough to rugose when young, with deep rugose when older, margins thick, concolorous with the thallus, shiny, verrucose and higher than disc when young, warts developing until they intersect with the folds of the disc at maturity. Pycnidia are absent. Hymenium hyaline, 410–483 μm high; paraphyses are branched, densely aggregated; epihymenium black brown (the colour disappears in a 10 % KOH solution), 103–125 μm high; hypothecium 50–75 μm high; coccoid green alga, algae forming a continuous layer in the margin and below the hypothecium; asci clavate, (280) 285–309 (312) × (66) 67–74 (75) μm (n = 10), 8 - spored. Ascospores (90) 97–116 (123) × (30) 33–35 (36) μm (n = 33), aseptate, hyaline, broadly ellipsoid.

Chemistry.

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

Material examined.

China • Guizhou Province, Zunyi City, Kuankuoshui National Nature Reserve , 28°14'14.51"N, 107°9'16.55"E, 1529 m elev., on bark, 17 November, 2023, Weiwei Zheng and Bo Liu, KKS 83 ( KUN-L 96619 , holotype) GoogleMaps ; • Qiandongnan Prefecture City, Leigongshan National Nature Reserve , 26°23'6.73"N, 108°12'11.11"E, 2054 m elev., on bark, 17 October, 2023, Shaobin Fu and Ze Yang, LGS 40 ( KUN-L 96620 ) GoogleMaps .

Notes.

Phylogenetic analysis indicates that O. kuankuoshuiensis and O. parellula are closely related. However, there is a 2.62 % (13 / 496 bp) difference in the ITS sequence between strain KKS 83 ( O. kuankuoshuiensis ) and strain KoLRI No. 018698 ( O. parellula ). Additionally, O. parellula is a saxicolous species characterised by a smooth apothecial margin and smaller spores (40–52.5 × 20–22.5 μm) ( Park et al. 2019).

Judging by the description of O. trochophora in Brodo (1991), O. kuankuoshuiensis is morphologically and chemically similar to this species. However, the latter has smaller spores (35–71 × (20) 23–35 (– 40) μm ( Brodo 1991). Sequence comparison between the two species shows an ITS difference of 12.58 % (62 / 493 bp) and an mtSSU difference of 2.99 % (21 / 703 bp) between O. kuankuoshuiensis (KKS 83) and O. trochophora (J. Vondrak 15442). Another morphologically similar species, O. longispora , is characterised by a thin thallus, smooth to slightly verrucose apothecial margins and the presence of lichesterinic and protolichesterinic acid ( Ren 2017). The ITS sequence difference between O. kuankuoshuiensis (KKS 83) and O. longispora (LGS 231-2) is 3.73 % (19 / 509 bp).