Acarospora impressula Th. Fr.

Acarospora impressula is Holarctic species known from Asia, Europe and North America on calcareous and non-calcareous rock, metal-rich rock, and roofing slates in full sun. Most collections of A. impressula in the Czech Republic are on diabase at low elevations below 300 m. It is also a high elevation species in the Alps.

Like A. atrata it forms a contiguous areolate crust up to 1 mm thick. It differs from A. atrata in having euamyloid hymenal gel, occasionally larger subconvex areoles, broadly ellipsoid ascospores (more than 2 µm wide), and thicker paraphyses (2–3 µm vs. 1.5–2.0 µm). Like A. atrata or A. insolata, the morphological species concept of A. impressula may be a complex of species.

taxonomic classification:

Ascomycota Lecanoromycetes Acarosporales Acarosporaceae Acarospora

Red List (Liška & Palice 2010):NT – near threatened
Red List (Malíček 2023):DD – data deficient

Occurrence in the Czech Republic

All records: 24, confirmed 0. One click on a selected square displays particular record(s), including their source(s).


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Altitude preferences

Distribution Timeline

Substrate type

Substrate preferences

© Botanický ústav AV ČR, v. v. i. 2020–2024