Immersaria venusta C.M. Xie & Xin Y. Wang, 2022

Xie, Cong-Miao, Wang, Li-Song, Zhao, Zun-Tian, Zhang, Yan-Yun, Wang, Xin-Yu & Zhang, Lu-Lu, 2022, Revision of Immersaria and a new lecanorine genus in Lecideaceae (lichenised Ascomycota, Lecanoromycetes), MycoKeys 87, pp. 99-132 : 99

publication ID

https://dx.doi.org/10.3897/mycokeys.87.72614

persistent identifier

https://treatment.plazi.org/id/B17CABFE-2CFD-5099-B528-ADB037E575CB

treatment provided by

MycoKeys by Pensoft

scientific name

Immersaria venusta C.M. Xie & Xin Y. Wang
status

sp. nov.

Immersaria venusta C.M. Xie & Xin Y. Wang sp. nov.

Figure 6a-d View Figure 6

Etymology.

The name " Immersaria venusta " refers to the beautiful appearance of the thallus.

Type.

China. Qinghai Province: Maqing Co., Xueshan Village , 4187 m elev., 34°37'N, 99°42'E, on rock, 11 Sept 2020, Li-Song Wang et al. 20-67969 (KUN-holotype) GoogleMaps .

Description.

Thallus areolate, brown, orange-brown, more or less rusty, continuous; areolae 0.5-1.3 mm across, flat or slightly convex, irregular, tending to rectangular, often cracked, sometimes pruinose; margin pruinose; prothallus not seen. Upper cortex ca. 38.0 μm thick, yellow brown granules pigmented; epinecral layer ca. 12.0 μm thick; algal layer ca. 128.0 μm thick, cells 5.0-10.0 × 5.0-7.5 μm in diam., round to ellipsoid. Apothecia frequent, crowded, immersed or isolated from areolae, 0.6-1.0 mm in diam.; disc black, flat, epruinose; margin reduced, sometimes developed. Exciple sometimes developed, ca. 35.0 μm wide, brown. Hymenium 92.0-113.0 μm thick, colourless; paraphyses ca. 2.0 μm wide, anastomosing; epihymenium 27.5-30.0 μm thick, brown; subhymenium ca. 62.0 μm thick, colourless; hypothecium brown. Asci Porpidia -type, cylindrical, eight-spored; ascospores 10.0-12.5 × 5.0-7.5 μm, ellipsoid, halonate. Conidiomata immersed, linear, black, margin pruinose; conidia not seen.

Chemistry.

Thallus K-, C-. Medulla I+ violet. Chemotype Ⅰ: Confluentic acid, often accompanied with 2'-O-methylmicrophyllinic acid. Chemotype Ⅱ: Planaic acid. Chemotype Ⅲ: none (rare).

Ecology and distribution.

In China, growing on quartz sandstone or granite at elevations of 3900-4300 m in the alpine zone. This species is known from Qinghai Province of China.

Notes.

Immersaria venusta is characterised by its yellow-brown, cracked areolae, its flat apothecia and brown epihymenium. It resembles Immersaria shangrilaensis by its cracked areolae, but its areolae have the tendency to split into several patches, but not aggregate like those of I. shangrilaensis . Immersaria athroocarpa is similar to I. venusta in the brown appearance of its thallus and in forming a sister group in the phylogenetic tree, but it differs in its yellow brown thallus, convex areolae, densely crowded apothecia and larger ascospores (17.5-20.0 × 10.0 μm). Immersaria venusta is also similar to I. aurantia (see notes for I. aurantia ). The brown thallus of Immersaria venusta possibly resembles that of I. olivacea , but the latter differs in its simple or one-septate ascospores, pyriform conidia and dark bluish-green epihymenium.

Specimens examined (KUN).

China. Qinghai Province: Maqing Co., Xueshan Village, 4187 m elev., 34°37'N, 99°42'E, on rock, 2020, Li-Song Wang et al. 20-67969, 20-67965; Banma Co. , Yaertang Village , 3930 m elev., 32°42'N, 100°42'E, Li-Song Wang et al. 20-66940 GoogleMaps . Sichuan Province: Shiqu Co., Xinrong Village, 4043 m elev., 32°59'N, 98°19'E, on rock, 2020, Li-Song Wang et al. 20-68802; Rangtang Co. , Mt. Haizi , 4246 m elev., 32°21'N, 101°24'E, Li-Song Wang et al. 20-66721, 20-66725 GoogleMaps .

Selected additional comparative material was examined.

Bellemerea alpina (Sommerf.) Clauzade & Cl. Roux Russia, Lps. Petsamo, Pummangin vuonon N-puoli, 1938, Räsänen, V., H9503269 (H); Lps. Petsamo, inter Vaitolahti et Kervanto, 1938, Räsänen, V., H9503270 (H).

Bellemerea cinereorufescens (Ach.) Clauzade & Cl. Roux Finland, Ob. Simo. Anteroinen. Rantakivellä, 1920, Räsänen, V., H9503267 (H); Le. Enontekiö, Kirkonkylä, 1925, Kari, L.E., H9503268 (H).

High-resolution photographs seen.

Immersaria carbonoidea (J.W. Thomson) Esnault & Cl. Roux USA, Alaska, along the Pitmegea River, 15 miles upstream from Cape Sabine, 1958, Thomson, J.W., M0082171 (M-isotype!), G00126754 (G-isotype!).

Immersaria olivacea Calat. & Rambold Spain, Espana, Castelló: Benicàssim, Parreta Alta, 390 m elev., 1993, Calatayud, V., M0101779 (M-isotype!).

Immersaria usbekica (Hertel) M. Barbero, Nav.-Ros. & Cl. Roux Algeria Algerie-Atlas Tellieu, Larba, Piste de Bougara á Tablat au S-E de l’arboretum de Meindja, 1985, Esnault, J., M0101787 (M-paratype!).