Acarospora microcarpa (Nyl.) Wedd.

Bull. Soc. Bot. France, 21: 343, 1874. Basionym: Lecanora schleicheri var. microcarpa Nyl. - Act. Soc. Linn. Bordeaux, 21: 327, 1857.
Synonyms: Acarospora kordofanica sensu Nimis & Poelt non Zahlbr. ex H. Magn.; Acarospora tersa (Fr.) J. Steiner
Distribution: N - TAA, Piem (TSB 10146). C - Tosc, Laz (Tretiach 2004), Sar (Rizzi & al. 2011). S - Camp, Si (Nimis & al. 1996b, Cataldo & Cannavò 2014).
Description: Thallus crustose, episubstratic, bright greenish yellow, epruinose, consisting of 0.2-1(-2) mm wide, scattered or clustered, flat, irregular, angular areoles, when well-developed forming up to 1-2 cm wide patches, usually starting the life-cycle on the thalli of Diploschistes actinostoma. Cortex paraplectenchymatous, 35-70 µm thick; algal layer continuous; medulla white. Apothecia lecanorine, 0.1-0.4 mm across, immersed in the areoles, 1-4(-8) per areole, with a dark brown, punctiform disc and an evident, not or only slightly raised thalline margin. Epithecium brownish; hymenium colourless, 120-140 µm high; paraphyses 1.5-2 µm thick at base; hypothecium colourless. Asci 100-200-spored, broadly ellipsoid, the apical dome K/I-. Ascospores 1-celled, hyaline, broadly ellipsoid, 3-6 x 2-3 µm. Photobiont chlorococcoid. Spot tests: K-, C-, KC-, P-. Chemistry: cortex with rhizocarpic acid.
Note: a mainly Mediterranean-Atlantic species, with optimum in coastal Tyrrhenian Italy, on base-rich siliceous rocks wetted by rain, growing on the thalli of speies of Diploschistes,, Acarospora, Dimelaena and Protoparmelia. The species also occurs in the dry-continental Alpine valleys.
Growth form: Crustose
Substrata: rocks
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: very rare
Humid mediterranean belt: rather rare
Dry mediterranean belt: extremely rare

pH of the substrata:


Solar irradiation:








Altitudinal distribution:


Predictive model
Herbarium samples

Domenico Puntillo; Owner: Domenico Puntillo
Italy, Puntillo 8351

P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Herbarium: TSB (17709)
on the host, Diploschistes actinostomus

P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Herbarium: TSB (17709)