Verrucaria alpigena Breuss, nom. nov., Sauteria 15: 122, 2008

Pykaelae, Juha, Kantelinen, Annina & Myllys, Leena, 2020, Taxonomy of Verrucaria species characterised by large spores, perithecia leaving pits in the rock and a pale thin thallus in Finland, MycoKeys 72, pp. 43-92 : 43

Verrucaria alpigena Breuss, nom. nov., Sauteria 15: 122, 2008

Type.

Austria, Niederösterreich, Voralpen, Bez. Lilienfeld, Gem. Kleinzell, SE von Salzerbad, Weg von Reintal zum Kruckensattel, 550-650 m alt., 29.3.2002, O. Breuss (8060) 19.990 (LI-01763881!, holotype).

Description.

Prothallus rather weakly developed, medium brown, weakly fimbriate. Thallus pale greyish-brown with frequent medium brown flecks, rimose, ca. 0.05-0.15 mm thick. Perithecia 0.22-0.38 mm, 1/2-3/4-immersed, not leaving pits to leaving shallow pits in the rock, thinly thalline covered except apex; ca. 80-100 perithecia cm2. Ostiole pale brown, plane, ca. 20-60 mm wide. Involucrellum to the exciple base level, occasionally enveloping the exciple, ca. 40-60 mm thick, appressed to the exciple. Exciple 0.21-0.24 mm in diam., wall pale to dark brown. Ascospores 0-septate, (22.7-)26.1-28.1- 30.9(-33.6) × (12.1-)12.4-13.5-14.5(-15.8) mm (n = 20).

Notes.

This species was erroneously reported from Finland by Pykälä (2011), but based on the ITS phylogeny, the specimen belongs to V. subjunctiva . It differs from the other Finnish specimens of V. subjunctiva by the pale exciple wall. Originally, V. alpigena was described as a species related to V. muralis , but differing by larger spores (Breuss 2008). Studying the type specimen of V. alpigena revealed that the species may not be related to V. muralis nor to the Thelidium group. It has a superficial morphological similarity to Verrucaria ahtii Pykälä, Launis & Myllys ( Pykälä et al. 2017), but the spores are larger. Verrucaria alpigena may belong to the so-called Endocarpon group such as V. ahtii .