Catillaria minuta (A. Massal.) Lettau

Hedwigia, 52: 135, 1912. Basionym: Biatorina minuta A. Massal. - Ric. Auton. Lich. Crost.: 137, 1852.
Synonyms: Biatorina arnoldii Kremp.; Biatorina arnoldii var. luteella (Nyl.) A.L. Sm.; Catillaria arnoldii (Kremp.) Th. Fr.
Distribution: N - VG (25437), Frl, Ven (Watson 2014), Lomb (Lazzarin 2000b), Emil (Fariselli & al. 2020). C - Tosc (Tretiach & al. 2008), Marc (Nimis & Tretiach 1999), Umb (Ravera & al. 2006). S - Camp (Nimis & Tretiach 2004), Pugl (Nimis & Tretiach 1999), Bas (Nimis & Tretiach 1999), Si (Nimis & al. 1994, 1996b).
Description: Thallus crustose, entirely endosubstratic, whitish or poorly evident. Apotecia lecideine, 0.2-0.3(-0.4) mm across, yellowish brown to pale reddish brown, sessile, with a concave, then flat to slightly convex disc, and an initially prominent and smooth, finally excluded proper margin which is usually paler than disc. Proper exciple pale yellow in outer part, colourless within; epithecium pale yellowish brown, K-; hymenium colourless, 45-60 µm high; paraphyses simple, the apical cells only slightly swollen, up to 2.5(-3) µm wide, weakly pigmented; hypothecium colourless to pale straw-coloured. Asci clavate, with a uniformly amyloid apical dome, Biatora-type. Ascospores 1-septate, slightly restricted at septum, hyaline, ellipsoid to ovoid-fusiform, (10-)12-16(-18) x 4-6.5 µm, the old ones with a microrugulate surface. Photobiont chlorococcoid. Spot tests: thallus K-, C-, KC-, P-, UV-. Chemistry: without lichen substances.
Note: a mild-temperate species found on steeply inclined or underhanging faces of compact limestones in sheltered situations, e.g. in narrow gorges along creeks.
Growth form: Crustose
Substrata: rocks
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly sexual
In underhangs rarely wetted by rain

Commonnes-rarity: (info)

Alpine belt: absent
Subalpine belt: absent
Oromediterranean belt: absent
Montane belt: very rare
Submediterranean belt: rare
Padanian area: absent
Humid submediterranean belt: rare
Humid mediterranean belt: extremely rare
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 24243

P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Herbarium: TSB (24243)