Hymenelia prevostii (Duby) Kremp.

Flora, 35: 25, 1852. Basionym: Urceolaria prevostii Fr. ex Duby - Bot. Gall., 2: 671, 1830.
Synonyms: Aspicilia prevostii (Duby) Anzi; Ionaspis prevostii (Duby) Arnold; Lecanora lithofraga (A. Massal.) Jatta; Lecanora prevostii (Duby) Th. Fr.
Distribution: N - Frl (Cucchi & al. 2009), Ven (Nascimbene & Caniglia 2003c), TAA (Nascimbene & al. 2022), Lomb, Piem (Isocrono & al. 2004), Emil (Fariselli & al. 2020), Lig. C - Tosc (Tretiach & al. 2008), Marc (Nimis & Tretiach 1999), Umb (Genovesi & Ravera 2001, Ravera & al. 2006), Laz (Nimis & Tretiach 2004), Mol (Nimis & Tretiach, 1999, 2004, Caporale & al. 2008), Sar. S - Camp (Aprile & al. 2003b, Nimis & Tretiach 2004, Garofalo & al. 2010), Pugl, Bas (Nimis & Tretiach 1999), Si (Nimis & al. 1994, Grillo & al. 2007).
Description: Thallus crustose, endosubstratic to episubstratic, continuous to finely rimose, cream-coloured, brownish or grey, without a distinct prothallus. Apothecia immersed in the thallus and often surrounded by a circular crack, 0.2-0.7 mm across, rounded or irregular in outline, with an initially concave, then flat, pink, yellow-pink or pale brown disc, and a rather evident, whitish proper margin. Proper exciple colourless; epithecium colourless or pale yellowish brown, K-, N-; hymenium colourless, 100-120 µm high; paraphyses simple or sparingly branched, submoniliform in upper part, the apical cells slightly swollen; hypothecium colourless. Asci 8-spored, cylindrical-clavate, the outer coat I+ blue, but the inner walls and apical dome K/I-. Ascospores 1-celled, hyaline, ellipsoid, 10-24(-26) x 7-17(-19) µm. Pycnidia immersed, pale-walled. Conidia short-bacilliform. Photobiont chlorococcoid (Asterochloris), the cells <15 µm wide. Spot tests: thallus K-, C-, KC-, P-, UV-. Chemistry: without lichen substances.
Note: on hard calcareous rocks, especially compact limestone, most frequent in the Alps, but also present in the Mediterranean mountains, probably occurring throughout the country. According to Lutzoni & Brodo (1995) and Roux & coll. (2014), this is just a phycotype of H. epulotica with trebuxioid algae.
Growth form: Crustose endolithic
Substrata: rocks
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly sexual

Commonnes-rarity: (info)

Alpine belt: very rare
Subalpine belt: rare
Oromediterranean belt: very rare
Montane belt: very rare
Submediterranean belt: extremely rare
Padanian area: absent
Humid submediterranean belt: extremely rare
Humid mediterranean belt: extremely rare
Dry mediterranean belt: absent

pH of the substrata:


Solar irradiation:








Altitudinal distribution:


Predictive model
Herbarium samples

Photo uploaded by Paul Cannon - CC BY-SA-NC - Source: https://fungi.myspecies.info/sites/fungi.myspecies.info/files/P4230455.jpg

P.L. Nimis CC BY-SA 04
TSB 26583

P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Herbarium: TSB (26583)

P.L. Nimis CC BY-SA 04
TSB 31000