Buellia triseptata A. Nordin

Bryologist, 102: 260, 1999.
Synonyms: Buellia lauri-cassiae auct. eur. non (Fée) Müll. Arg.; Buellia triphragmia auct. non (Nyl.) Arnold
Distribution: N - TAA (Nascimbene & al. 2007b), Piem, Lig (Watson 2014). S - Camp, Bas (Ravera & al. 2015d).
Description: Thallus crustose, episubstratic, of variable thickness, continuous to rimose-areolate, whitish, whitish-grey to greyish green, with a smooth to irregular surface, rarely granulose-verrucose. Cortex with numerous crystals of atranorin, sometimes overlain with a thin epinecral layer; medulla white, not amyloid, I-. Apothecia lecideine, at first immersed, later adnate, up to 0.7 mm across, with a black, epruinose, flat to slightly convex disc (strongly convex only in overmature apothecia), and a thin, entire, slightly prominent proper margin. Proper exciple dark reddish brown, more or less uniformly pigmented, K-, N-; epithecium dark brown; hymenium colourless, 70-90 µm high, not inspersed with oil droplets; paraphyses 1.5(-2) µm thick in lower part, the apical cells (3-)4-5 µm wide, with a brown cap; hypothecium dark reddish brown. Asci 8-spored, Bacidia-type. Ascospores 3-septate, brown, mostly curved, ellipsoid with rounded to rarely slightly pointed ends, the middle septum thickened in young spores, (14-)16-19(-21) x 5.5-7(-9) µm, with ontogeny of type A. Photobiont chlorococcoid. Spot tests: thallus K+ yellow, C-, KC-, P+ faintly yellow. Chemistry: atranorin.
Note: mainly lignicolous, more rarely on the bark of conifers in upland areas: a critical taxon, which needs further study (see Nimis 1993: 145). The species is included in the Italian red list of epiphytic lichens as “Critically Endangered” (Nascimbene & al. 2013c).
Growth form: Crustose
Substrata: lignum
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly sexual
Poorly known taxon in need of further study

Commonnes-rarity: (info)

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


pH of the substrata:

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Solar irradiation:

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Aridity:

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Eutrophication:

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Poleotolerance:

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Altitudinal distribution:

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Curtis Randall Björk – CC BY-SA 4.0
Idaho, Idaho County, Salmon River Canyon, near Lucile Photographed from specimen (Björk 7222, UBC), on Celtis in deep canyon Date: 2002-02-02



P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Herbarium: TSB (26711)
2003/03/12