Gyalecta hypoleuca (Ach.) Zahlbr.

Cat. Lich. Univ., 2: 711, 1924. Basionym: Urceolaria hypoleuca Ach. - Meth. Lich.: 149, 1803.
Synonyms: Gyalecta gyalectoides (A. Massal.) Lindau; Gyalecta thelotremoides (Nyl.) Kremp.; Petractis hypoleuca (Ach.) Vězda; Secoliga gyalectoides (A. Massal.) A. Massal.; Thelotrema gyalectoides A. Massal.; Thelotrema gyalectoides var. exanthemoides A. Massal.; Volvaria gyalectoides (A. Massal.) Trevis.
Distribution: N - Frl (Henssen & Tretiach 1995, Breuss 2008), Ven (Lazzarin 2000b, Nascimbene 2008c), TAA (Nascimbene 2008b), Lomb, Lig (Watson 2014). C - Tosc (Tretiach & al. 2008), Marc (Nimis & Tretiach 1999). S - Camp (Garofalo & al. 2010), Pugl, Cal (Puntillo 1996).
Description: Thallus crustose, episubstratic, 200-400 µm thick, continuous to rimose, pale yellowish white to pinkish white. Apothecia 0.3-0.6 mm across, urceolate, half-immersed, at first covered by a thalline layer and appearing perithecioid, later erumpent and with a concave to flat, orange-red to flesh-coloured disc, and a usually smooth, thick, convex proper margin. Proper exciple 10-35 µm wide; hymenium colourless, 120-170 µm high; paraphyses thread-like, inspersed with oil droplets and granules; hypothecium poorly developed. Asci 8-spored, cylindrical, thin-walled, without a tholus. Ascospores 5-9-septate (rarely with an additional longitudinal septum), hyaline, narrowly fusiform, straight or slightly curved, 20-38 x 4.5-7 µm, not halonate. Photobiont trentepohlioid. Spot tests: K-, C-, KC-, P-, UV-. Chemistry: without lichen substances.
Note: a cool-temperate species found on steeply inclined to underhanging faces of dolomitic rocks and limestone in rather sheltered situations, mostly in woodlands.
Growth form: Crustose
Substrata: rocks
Photobiont: Trentepohlia
Reproductive strategy: mainly sexual
In underhangs rarely wetted by rain

Commonnes-rarity: (info)

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

pH of the substrata:


Solar irradiation:








Altitudinal distribution:


Predictive model
Herbarium samples

P.L. Nimis CC BY-SA 4.0
TSB 35426

P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Herbarium: TSB (17181)

P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Herbarium: TSB (16899)

P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Herbarium: TSB (35426)