Myriostigma xanthominiatum Aptroot & M.F. Souza, 2021

Aptroot, André & Souza, Maria Fernanda, 2021, New crustose lichens from a tropical coastal area in Paraná (Brazil), Cryptogamie, Mycologie 20 (12), pp. 191-197 : 196

publication ID	https://doi.org/ 10.5252/cryptogamie-mycologie2021v42a12
DOI	https://doi.org/10.5281/zenodo.7815221
persistent identifier	https://treatment.plazi.org/id/03B8746C-FFE9-FF9E-F373-FE28FC84FA2C
treatment provided by	Felipe
scientific name	Myriostigma xanthominiatum Aptroot & M.F. Souza
status	sp. nov.

Treatment

Myriostigma xanthominiatum Aptroot & M.F. Souza View in CoL , sp. nov.

( Fig. 1 View FIG D-F)

Corticolous Myriostigma with thallus whitish ochraceous, containing lichexanthone, ascigerous areas delimited, black with orange pruina, ascospores 8/ascus, ellipsoid, hyaline, muriform, c. 12 × 10-septate, 85-94 × 35-39 µm, central lumina much larger (c. 10 µm diam.) than lumina near the wall.

MYCOBANK. — MB839448.

TYPE. — Brazil, Paraná, Guaraqueçaba, Tagaçaba Porto da Linha , road PR- 405 km 36.2, at right side of road, in chácara (property of Donald Schause), 14.X.2020, alt. 15 m, on tree bark, A. Aptroot & M.F. Souza 82089 (holo-, CGMS; iso-, ABL).

ADDITIONAL MATERIAL STUDIED. — Same details, M.F. Souza & A. Aptroot 291 ( CGMS).

CHEMISTRY. — Thallus C-, K-, P-, UV+ yellow, with lichexanthone; ascigerous areas K+ red and UV+ red, with an unidentified anthraquinone (Rf 1 TDA, pale orange yellow in acetone solution).

DESCRIPTION

Thallus corticolous,whitish ochraceous,dull, somewhat granular and variable in thickness up to c. 0.2 mm thick, covering an area of up to 10 cm diam., surrounded by a c. 0.2 mm wide black prothallus line.Algae trentepohlioid, orange, c. 10-15 µm diam. Ascigerous areas delimited, IKI negative, patchy, roundish to irregularly lirelline, black spots with orange pruina, up to 2 mm long and 0.7 mm wide, c. 0.2-0.3 mm high, covering about a quarter of the thallus surface. Asci globose, hyaline, containing 8 ascospores, 100-125 µm diam, wall up to 15 µm thick. Ascospores ellipsoid, hyaline, muriform, c. 12 × 10-septate, 85-94 × 35-39 µm, central lumina much larger (c. 10 µm diam.) than lumina near the wall. Pycnidia not observed.