Thelidium sp. 1

Pykaelae, Juha, Kantelinen, Annina & Myllys, Leena, 2023, Taxonomy of Thelidium auruntii and T. incavatum complexes (lichenized Ascomycota, Verrucariales) in Finland, MycoKeys 96, pp. 1-23 : 1

Thelidium sp. 1

Description.

Prothallus not visible. Thallus whitish grey, endolithic. Perithecia 0.25-0.33 mm in diam., 1/4-1/2-immersed, leaving shallow pits; c. 50 perithecia / cm2. Ostiole, tiny, dark, plane. Involucrellum almost to the exciple base, 30-50 μm thick, may thicken to the base to c. 50-60 μm thick, slightly diverging from the exciple. Exciple c. 0.17-0.25 mm, wall dark brown. Periphysoids c. 25-30 × 2 μm. Asci 8-spored. Ascospores 0-1-septate, 23-28 × 10-12 μm.

Habitat and distribution.

The specimen has been collected from a dolomite rock outcrop on a fell in northern Finland in Enontekiö.

Notes.

The specimen probably represents an undescribed species belonging to the T. auruntii complex. However, the specimen is quite small, and thus, better material is needed.

Specimen examined.

Finland, Enontekiön Lappi, Enontekiö, Porojärvet, Toskalharji, Toskaljärvi N, fell, dolomite rock outcrop, on SW-slope, 715 m a.s.l., 69°11'N, 21°26'E, 2 August 2011, J. Pykälä 43208 (H).