Lichenostigma alpinum
Stromata medium to dark reddish brown, with a verrucose to sometimes indistinctly mosaic-like ornamentation.
Anamorph: conidiomata frequent, (20–) 25–100 (−150) μm diam. Conidia (10–) 11–13.5 (−15) × (7–) 8.5–10.5 (−12) μm, ± spherical to ellipsoidal, composed of (4–) 8–17 (−22) smooth, rarely verrucose cells [in optical section (4–) 6–10 (−12) cells], the cells (3–) 3.5–5 (−6) μm diam., dark brown, ± smooth.
Teleomorph: not definitely known; two separate taxa have been linked to this species.
Description adapted from Ertz et al. (2013).
Assessed by Woods & Coppins (2012) as of Least Concern, but listed as Nationally Rare.
Collections identified as this species on Lecanora species should probably be referred to L. chlaroterae. Lichenostigma sp. P4194 appears to be distinct; it has a rather different colony structure with radiating superficial hyphae.
The species probably represents an aggregate; Ertz et al. (2013) observed that a collection on Phaeographis from France probably represents a separate species. Material on this genus from Devon appears morphologically similar to the type of L. alpinum, though it has patches of K/I blue coloration in the conidiomata similar to those described for Etayoa trypthelii (a widespread, mainly tropical species on Graphidaceae), but that has rough-walled conidia compared with the smooth conidia seen in the L. alpinum aggregate.
Biotrophic on thalli of Ochrolechia and Pertusaria species.
Scattered throughout Scotland and SW England, probably under-recorded.