Heteroplacidium imbricatum (Nyl.) Breuss

Ann. naturhist. Mus. Wien, 98B: 40, 1996. Basionym: Endocarpon imbricatum Nyl. - Bot. Not.: 161, 1853.
Synonyms: Catapyrenium imbricatum (Nyl.) Clauzade & Cl. Roux; Dermatocarpon imbricatum (Nyl.) Zahlbr.; Endopyrenium imbricatum (Nyl.) Boistel
Distribution: N - VG, Frl (TSB 3062), Ven, Lig. C - Tosc, Umb (Genovesi & al. 2001, Ravera & al. 2006), Sar. S - Camp (Nimis & Tretiach 2004), Si (Nimis & al. 1996b, Grillo & Caniglia 2004, Caniglia & Grillo 2005, Cataldo & Minissale 2015).
Description: Thallus squamulose, pale greyish brown to brownish, dull, rarely faintly pruinose at margin. Squamules 1-3 mm broad, 0.15-0.4 mm thick, rounded to crenulate, concave to convex, but usually flattened, smooth, densely imbricate, forming 2-4 cm wide cushions. Lower surface whitish to yellowish white or very pale brown, attached by 4-5 μm thick, pale rhizohyphae which are usually present only at the base of squamules. Upper cortex paraplectenchymatous 20-40 μm thick, of 4-13 μm wide, angular cells; medulla of globose cells; lower cortex not clearly delimited from the medulla. Perithecia rather rare, laminal, subglobose to pyriform, immersed, to 0.35 mm broad, without involucrellum. Exciple initially pale, then brown, finally dark brown to black; paraphyses absent, substituted by periphyses. Asci 8-spored, unitunicate, clavate, not or only slightly thickened at apex, without ocular chamber, the wall I-. Ascospores 1-celled, hyaline, biseriately arranged in the asci, narrowly ellipsoid, thin-walled, (11-)12-16(-17) x 5-7 μm. Pycnidia dark, immersed. Conidia subcylindrical, 4-5 x c. 1 μm. Photobiont chlorococcoid. Spot tests: cortex and medulla K-, C-, KC-, P-, UV-. Chemistry: without lichen substances.
Note: in fissures of hard calcareous rocks and amongst mosses, especially limestone, in rather sheltered situations, at low elevations.
Growth form: Squamulose
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly sexual

Commonnes-rarity: (info)

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

pH of the substrata:


Solar irradiation:








Altitudinal distribution:


Predictive model
Herbarium samples

P.L. Nimis CC BY-SA 4.0
TSB 2324

P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Herbarium: TSB (2324)