Verrucaria koerberi Hepp, Flechten Eur. 692, 1860

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 koerberi Hepp, Flechten Eur. 692, 1860

Type.

[Germany] an Dolomitfelsen in Laubwäldern bei Eichstätt (Baiern), F. Arnold, Hepp, Flechten Eur. 692 (UPS-L-069713!, syntype).

Description.

Prothallus not seen. Thallus white, endolithic to thinly epilithic. Perithecia 0.2-0.3 mm, 3/4-1-immersed, leaving deep pits in the rock, surrounded by a thalline collar, ca. 50-120 perithecia/cm2. Ostiole inconspicuous, dark, depressed, ostiolar depression up to 100 mm wide. Involucrellum apical, 40-70 mm thick, appressed to the exciple. Exciple 0.17-0.25 mm in diam., wall dark. Periphysoids ca. 30 × 1.5 mm. Ascospores 0-septate, (17-)18-21 × (7-)8 mm.

Notes.

This species differs from V. subtilis in smaller spores. The specimen H-NYL 7012 does not belong to the type material because it has too large spores (25-33 × 12-16 mm).