Microcalicium arenarium (A. Massal.) Tibell

Bot. Not., 131: 237, 1978. Basionym: Cyphelium arenarium Hampe ex A. Massal. - Miscell. Lichenol.: 20, 1856.
Synonyms: Calicium arenarium (A. Massal.) Körb.; Calicium citrinum (Leight.) Nyl.; Calicium gneissicum Nyl.; Calicium pulverariae Auersw.; Coniocybopsis arenaria (A. Massal.) Vain.
Distribution: N - TAA (Puntillo & Puntillo 2009, Brackel 2016), Piem (Isocrono & al. 2004, Puntillo & Puntillo 2009, Brackel 2016). C - Umb (Genovesi & al. 2001, Ravera & al. 2006, Puntillo & Puntillo 2009, Brackel 2016). S - Cal (Puntillo 1994, 1995, 1996, Puntillo & Puntillo 2009, Brackel 2016).
Description: Thallus not evident, not lichenized. Apothecia long-stalked, 0.8-1.6 mm high. Stalk black or dark grey, smooth or coarsely granular from clusters of sclerotized hyphae, the inner part consisting of irregularly interwoven, thick-walled hyphae. Capitulum spherical, 0.2-0.3 mm across. Excipulum poorly developed, reddish brown in section, forming a small basal collar; paraphyses not sclerotized, dissolving early; mazaedium well-developed, protruding, green-black. Asci broadly ellipsoid, with a single functional wall layer, formed in chains, disintegrating early. Ascospores 1-septate, broadly ellipsoid, 6-7 x 2-2.5 µm, with a distinct ornamentation of spirally arranged ridges. Photobiont absent. Spot tests: K-, C-, KC-. P- (but green pigment in maezaedium and exciple react K+ yellowish brown). Chemistry: without lichen substances.
Note: on silicicolous lichens, soil, rootlets, decorticated stumps and algal colonies in underhangs of siliceous rocks, often together with Psilolechia lucida; probably more widespread in the Alps than the few records would suggest.
Growth form: Fungus
Substrata: rocks
Reproductive strategy: mainly sexual
In underhangs rarely wetted by rain

Commonnes-rarity: (info)

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

pH of the substrata:


Solar irradiation:








Altitudinal distribution:


Predictive model
Herbarium samples

Domenico Puntillo CC BY-SA 4.0
Calabria. Cosenza, Cerzeto

P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Herbarium: TSB (14650)

P.L. Nimis - CC BY-SA 4.0
TSB 42008

Domenico Puntillo - CC BY-SA 4.0
Italia. Calabria. Cosenza, Cerzeto 01/05/1991