Lobothallia cheresina var. microspora (Arnold)

Provisionally placed here, ICN Art. 36.1b.. Basionym: Aspicilia calcarea var. microspora Arnold in Glowacki - Verh. zool.-bot. Ges. Wien, 20: 450, 1870.
Synonyms: Aspicilia cheresina var. microspora (Arnold) Clauzade & Cl. Roux; Aspicilia microspora (Arnold) Hue
Distribution: N - VG, Lig (Valcuvia & al. 2000). C - Marc (Nimis & Tretiach 1999), Laz (Nimis & Tretiach 2004), Abr (Nimis & Tretiach 1999), Sar.
Description: Thallus crustose, episubstratic, continuous to cracked at the periphery, areolate in central parts, very well delimited (sometimes by a black prothallus), forming orbicular patches on the thalli of Circinaria calcarea; the marginal part of the thallus is often radially cracked, giving it an almost placodioid appearance. Areoles angular, flat, smooth, white to pale grey. Apothecia lecanorine-aspicilioid, 0.2-1 mm across, irregular in outline, from round to elongate or angular, immersed in the areoles, with a black, often grey-pruinose, concave to flat, smooth disc, and a very slightly raised thalline margin. Epithecium greenish brown; hymenium colourless; paraphyses more or less branched and anastomosing; hypothecium colourless, subtended by a continuous algal layer. Asci (6-)8-spored, clavate, the thin outer coat K/I+ blue, the wall and apical dome K/I-, Lecanora-type. Ascospores 1-celled, hyaline, broadly ellipsoid, 8-14 x 5-10 μm, 1-2 seriate in the asci. Pycnidia immersed, black, the wall colourless in sections except around the ostiole. Conidia bacilliform, 4-5 x c. 1 μm. Photobiont chlorococcoid. Spot tests: thallus K+ yellow, then blood-red (needle-like crystals), C-, KC-, P+ yellow, UV-. Chemistry: norstictic acid.
Note: a southern European and Mediterranean-montane, very characteristic but often overlooked lichen described from Egypt; it is found on calcareous rocks, starting the life-cycle on Circinaria calcarea and related species; this is the chemotype with norstictic acid only.
Growth form: Crustose placodiomorph
Substrata: rocks
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly sexual
paras Circinaria calcarea s.lat.

Commonnes-rarity: (info)

Alpine belt: absent
Subalpine belt: absent
Oromediterranean belt: rare
Montane belt: rather rare
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

Pier Luigi Nimis - CC BY-SA 4.0
TSB 32327

P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Herbarium: TSB (23759)
well developed thallus

P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Herbarium: TSB (24469)