Lobothallia hedinii (H. Magn.) Paukov

Wang, Lun, Feng, Yi-Shan, Wang, Li-Song, Wang, Xin-Yu & Zhang, Yan-Yun, 2025, An overview of the genus Lobothallia (lichenized Ascomycota, Megasporaceae) in China, MycoKeys 125, pp. 205-244 : 205-244

Lobothallia hedinii (H. Magn.) Paukov , Lichenologist 51 (4): 312 (2019).

Fig. 11

Basyonym.

Lecanora hedinii H. Magn. Lichens from Central Asia 1: 98 (1940).

Holotype.

China • Gansu Prov.: Eh-ma-ta-ch’üan , 1931, Bohlin 55 a ( S) .

Description.

Thallus tightly adnate to the substrate, 3–6 cm across (up to 10 cm in intact field specimens), centrally areolate, 3–4 mm thick, marginally lobate, 0.4–1 mm thick. Areoles angular to irregular, not constricted at base, (0.4 –) 0.6–1 (– 1.8) mm wide, interspaces between areoles 0.05–0.2 mm wide. Lobes simple, rarely dichotomous, parallel-arranged, (1.5 –) 2–3 (– 4) mm long, 0.5–1.5 (– 2) mm wide. Upper surface plane to slightly convex, gray or pale brown to brownish red, pruinose, pruina usually thicker on the margin of areoles and lobes. Upper cortex paraplectenchymatous, 25–40 μm thick, containing brown granules (soluble in K); epinecral layer 10–15 µm thick, with dark granules (partly soluble in K). Algal layer 125–200 µm thick, discontinuous; photobiont chlorococcoid, cells 10–20 µm diameter. Medulla 0.5–2.5 (– 3) mm high, filled with gray-black granules (insoluble or partly soluble in K). Lower cortex absent.

Apothecia numerous, initially cryptolecanorine, becoming lecanorine at maturity, 1–3 per areole, adnate, orbicular to slightly angular by pressure, (0.2 –) 0.4–1.5 (– 2.2) mm wide; disc matt, brown to black, pruinose, concave to plane; apothecial margin entire, concolorous with thallus, 0.05–0.2 mm wide. Exciple narrow, widening to 50–80 μm in the uppermost part. Epithecium, hymenium and subhymenial layers combined 125–150 µm high; epithecium 10–15 µm high, with plate-like crystals; epihymenium filled with brown granules (soluble in K), N –; hymenium 75–100 µm high, hyaline, I + blue; subhymenial layers 40–50 μm high, hyaline, I + blue; algal layer beneath hypothecium discontinuous; paraphyses simple, septate, submoniliform at the tips, with 2–4 uppermost cells shorter and wider than the basal cells, 4–5 μm wide (basal cells ca. 2 μm wide); asci clavate, Aspicilia - type, hyaline, 8 - spored, 65–75 × 20–30 µm; ascospores simple, hyaline, broadly ellipsoid to ellipsoid, (11.0 -) 12.5–13.5 – 14.5 (- 16.0) × (8.0 -) 8.4–9.2 – 9.9 (- 11.0) µm (n = 33), l / w ratio (1.2 -) 1.3–1.5 – 1.7 (- 1.9), wall ca. 1 µm thick. Pycnidia common, punctiform when young, slightly protruding at maturity, 0.1–0.2 (– 0.5) mm in diameter; ostioles brown to black; conidia bacilliform, hyaline, 5–6 × 1 µm.

Chemistry.

Cortex K + yellow, P –; medulla K + yellow to orange-red, P + yellow, C –, KC –; containing norstictic and connorstictic acids, cryptostictic acid also detected in one specimen.

Habitat and distribution.

Saxicolous. Currently known from Gansu, Qinghai and Xizang Provinces, China.

Notes.

The species was originally described from Gansu Province, China. Our integrated phenotypic and genotypic analyses confirmed its phylogenetic placement for the first time and extended its known distribution to Qinghai and Xizang. Although variable in thallus color, this species can be easily recognized by its areolate thallus with straight and parallel-arranged lobes, and production of norstictic and constictic acids. Its phylogenetic sister species, Lobothallia polypycnidiata , resembles L. hedinii but differs in having multiple pycnidia per areole, lobes with a slightly broader margin, and the P – or P + pale yellow (only near the algal layer) medullary spot-reaction, contrasting with the distinct P + yellow reaction in L. hedinii . Lobothallia praeradiosa shares production of norstictic and connorstictic acids with L. hedinii but differs in its curved and overlapping marginal lobes, gray or orange-brown upper surface, lecanorine apothecia, epruinose discs, and the orange-brown apothecial margins ( Magnusson 1940; Kou et al. 2013; Paukov et al. 2019).

Additional specimens examined.

China • Gansu Prov.: Yumen City, Yu’erhong Vi. , 39°39'29.84"N, 97°10'45.88"E, alt. 3044 m, on rock, 27 May 2018, Li-Song Wang et al. 18-59518 ( KUN-L 62904 ), 18-59517 ( KUN-L 62903 ) • Sunan Yugur Autonomous Co., Dahe Vi. , 38°51'29.84"N, 99°38'55.16"E, alt. 2265 m, on sandstone, 6 July 2022, An-Cheng Yin and Han-Xiang Chen 22-72380 ( KUN-L 87006 ) • Qinghai Prov.: Haixi Prefecture, Dulan Co., Xiangjia Vi. , 36°00'53.98"N, 97°44'35.61"E, alt. 3036 m, on rock, 15 September 2020, Xin-Yu Wang et al. XY 20-2969 ( KUN-L 79324 ) • Dulan Co., S. B. Zhang ZSB 24-1727 ( KUN-L), Dulan-64 ( KUN-L) • Golmud City , 35°53'06.05"N, 94°28'22.55"E, alt. 3665 m, on rock, 16 September 2020, Li-Song Wang et al. 20-68298 ( KUN-L 76479 ), 20-68279 ( KUN-L 76460 ) • Delingha City , S. B. Zhang Dacaidan-9 ; Hainan Prefecture, Gonghe Co., 36°46'21.59"N, 99°38'47.62"E, 3456 m, Li-Song Wang et al. 18-58220 ( KUN-L 61713 ) • Tianjun Co., 37°38'24"N, 98°37'29"E, alt. 3581 m, on rock, 1 January 2023, S. B. Zhang and H. L. Kang ZSB 23-410 ( KUN-L 83735 ) • Yushu Tibetan Autonomous Prefecture, Zaduo Co., 32°52'43.73"N, 95°20'28.82"E, alt. 4083 m, on sandstone, 20 September 2020, Li-Song Wang et al. 20-68620 ( KUN-L 76802 ) • Golog Tibetan Autonomous Prefecture, Gande Co., 33°50'29.51"N, 99°40'33.09"E, alt. 3986 m, on rocks, 13 September 2020, Li-Song Wang et al. 20-68152 ( KUN-L 76332 ), 20-68147 ( KUN-L 76327 ), S. B. Zhang ZSB 24-1730 ( KUN-L) • Xizang Autonomous Region: Sakya Co., Jiding Town , 29°12'01.18"N, 88°23'10.59"E, alt. 3941 m, on calcareous rocks, 14 June 2022, Li-Song Wang et al. 22-71169 ( KUN-L 85793 ), 22-71155 ( KUN-L 85779 ) • Qushui Co., Qushui Town , 29°23'03.77"N, 90°50'03.23"E, alt. 3580 m, on rocks, 17 July 2019, Li-Song Wang et al. 19-64640 ( KUN-L 69137 ) .

Figures

Figure 11. Lobothallia hedinii A, B. Grey upper surface (20-68298, 20-68147); C. Pale brown to brownish red upper surface (18-59518). D – O. Detail characteristics of 18-59518: D. Thallus; E. Lobes; F. Apothecia; G. Pycnidia; H, I. Cross-section of thallus (below in K); J. Vertical section of pycnidia; K. Vertical section of apothecium; L. Vertical section of apothecium (LCB); M. Ascus and ascospores; N. Paraphyses (LCB); O. Conidia. Scale bars: 1 mm (D); 0.25 mm (E, F, G); 100 µm (H, I); 50 µm (J, K, L); 10 µm (M); 5 µm (N, O).