Bacidia polychroa (Th. Fr.) Körb.
Parerga Lichenol.: 131, 1860. Basionym: Biatora polychroa Th. Fr. - Öfvers. K. Svensk. Vetensk.-Akad. Förh., 12, 1: 17, 1855.
Synonyms: Bacidia acerina (Ach.) Arnold non auct.; Bacidia fuscorubella (Hoffm.) Bausch; Bacidia polysita (Stirt.) A.L. Sm.; Lecidea acerina (Ach.) Röhl.; Lecidea luteola var. fuscorubella (Hoffm.) Ach.; Secoliga fuscorubella (Hoffm.) Stizenb.; Verrucaria fuscorubella Hoffm. nom. inval.
Distribution: N - TAA (Nascimbene & al. 2007b, 2022, Nimis & al. 2015), Lomb, Emil (Fariselli & al. 2020). C - Mol (Paoli & al. 2015). S - Camp (Nimis & Tretiach 2004).
Description: Thallus crustose, episubstratic, continuous, rimose or finely warted-areolate, whitish to grey or yellowish grey. Apothecia lecideine, (0.4-)0.6-0.8(-1.2) mm across, brown-orange to purplish brown, often darkening with age, with a flat to finally convex, epruinose or white-pruinose disc, and a concolorous or slightly darker, at first thick and raised, finally excluded proper margin. Proper exciple 45-95 μm wide laterally, without crystals or with radiating clusters of minute crystals, pale yellowish brown, orange-brown to dark brown, K+ purple-red in outer and upper parts, often slightly paler within and colourless in lower parts; epithecium pale brown, scarcely differentiated from the hymenium; hymenium (56-)63-94(-100) μm high, colourless or very pale brown-orange in lower part, the upper part concolorous or (rarely) deep brown-orange; paraphyses 1-1.6 μm thick at mid-level, the apical cells not thickened or up to 3 μm wide; hypothecium brown-orange to dark brown, darker than exciple. Asci 8-spored, clavate to cylindrical-clavate, the apical dome K/I+ dark blue with a pale, conical-pointed apical cushion (axial mass), the wall K/I-, but the thin outer gel K/I+ blue, Bacidia-type. Ascospores (3-)7-15-septate, hyaline, acicular, straight to sigmoid, (38-)43-57(-74) x (2-)3-4(-5) μm. Pycnidia immersed, pale brown around the ostiole. Conidia simple, filiform, curved, 10-18(-20) x 0.6-0.8 μm. Photobiont chlorococcoid, the cells 5-12 μm in diam. Spot tests: thallus K-, C-, KC-, P-, UV-; pigmented parts of apothecia K+ purple-violet, N-. Chemistry: thallus without lichen substances or with traces of atranorin; apothecia with the Bacidia-brown and Rubella-orange pigments.
Note: a mild-temperate to tropical species found on broad-leaved trees in open, humid forests. It is included in the Italian red list of epiphytic lichens as “Endangered” (Nascimbene & al. 2013c).
Growth form: Crustose
Substrata: bark
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly sexual
Most common in areas with a humid-warm climate (e.g. most of Tyrrenian Italy)
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: extremely rare
Humid mediterranean belt: extremely rare
Dry mediterranean belt: absent

Predictive model
Herbarium samples


Felix Schumm - CC BY-SA 4.0
[20555], U.S.A., Minnesota, Mahnomen County, East of Washington Lake (18 miles NE of Mahnomen). In swamp area with balsam fir, spruce, tamarack, on ash. Leg. C. M. Wetmore (26401), 11.8.1976.


Felix Schumm - CC BY-SA 4.0
[20569], U.R.S.S., Transcaucasus, Colchis; distr. Sochi, in monte Achun, 600-650 m. Ad corticem Sorbi torminalis. Leg. A. Vezda, 17.06.1979.


Felix Schumm - CC BY-SA 4.0
[20569], U.R.S.S., Transcaucasus, Colchis; distr. Sochi, in monte Achun, 600-650 m. Ad corticem Sorbi torminalis. Leg. A. Vezda, 17.06.1979.


Felix Schumm - CC BY-SA 4.0
[20569], U.R.S.S., Transcaucasus, Colchis; distr. Sochi, in monte Achun, 600-650 m. Ad corticem Sorbi torminalis. Leg. A. Vezda, 17.06.1979.


Felix Schumm - CC BY-SA 4.0
[20555], U.S.A., Minnesota, Mahnomen County, East of Washington Lake (18 miles NE of Mahnomen). In swamp area with balsam fir, spruce, tamarack, on ash. Leg. C. M. Wetmore (26401), 11.8.1976.


Felix Schumm - CC BY-SA 4.0
[ABL80144], Brazil, Mato Grosso do Sul, Jateí, Parque Estadual das
Várzeas do Rio Ivinhema, in marsh forest on tree bark. 22°55’ S, 53°44’
W, 230 m. Leg. A. Aptroot (no 80144), 27.09.2019, det. A. Aptroot,
2019.
Growth form: Crustose
Substrata: bark
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly sexual
Most common in areas with a humid-warm climate (e.g. most of Tyrrenian Italy)
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: extremely rare
Humid mediterranean belt: extremely rare
Dry mediterranean belt: absent

Predictive model
| Herbarium samples |

Felix Schumm - CC BY-SA 4.0
[20555], U.S.A., Minnesota, Mahnomen County, East of Washington Lake (18 miles NE of Mahnomen). In swamp area with balsam fir, spruce, tamarack, on ash. Leg. C. M. Wetmore (26401), 11.8.1976.

Felix Schumm - CC BY-SA 4.0
[20569], U.R.S.S., Transcaucasus, Colchis; distr. Sochi, in monte Achun, 600-650 m. Ad corticem Sorbi torminalis. Leg. A. Vezda, 17.06.1979.

Felix Schumm - CC BY-SA 4.0
[20569], U.R.S.S., Transcaucasus, Colchis; distr. Sochi, in monte Achun, 600-650 m. Ad corticem Sorbi torminalis. Leg. A. Vezda, 17.06.1979.

Felix Schumm - CC BY-SA 4.0
[20569], U.R.S.S., Transcaucasus, Colchis; distr. Sochi, in monte Achun, 600-650 m. Ad corticem Sorbi torminalis. Leg. A. Vezda, 17.06.1979.

Felix Schumm - CC BY-SA 4.0
[20555], U.S.A., Minnesota, Mahnomen County, East of Washington Lake (18 miles NE of Mahnomen). In swamp area with balsam fir, spruce, tamarack, on ash. Leg. C. M. Wetmore (26401), 11.8.1976.

INDEX FUNGORUM
GBIF
DOLICHENS