Biatora rufidula (Graewe) S. Ekman & Printzen

in Printzen, Bibl. Lichenol., 60: 115, 1995. Basionym: Bilimbia rufidula Graewe in Hellbom - Öfvers. K. Svensk. Vetensk.-Akad. Förh., 24: 270, 1867.
Synonyms: Bacidia rufidula (Graewe) Zahlbr.; Lecidea rufidula (Graewe) Stizenb.
Distribution: N - TAA (Printzen 1995, Nascimbene & al. 2007b).
Description: Thallus crustose, endosubstratic or thinly episubstratic, whitish grey to greenish grey, 40-100 μm thick, continuous to rimose, rarely consisting of flat to slightly convex areoles. Cortex 12-30 μm thick colourless; medulla absent. Apothecia biatorine, rounded or irregular in outline, rarely tuberculate, sessile and constricted at base, 0.25-0.4(-0.6) mm across, with a ochre to chestnut-brown, flat to slightly convex, epruinose disc, and a pale beige to orange-brown, persistent or finally excluded proper margin. Proper exciple colourless or orange-brown within, I+ pale violet, 30-75 μm wide laterally, 40-155 μm wide basally, of radiating hyphae with 1-1.5 μm wide cylindrical lumina, the lumina of apical cells to 3 μm wide; epithecium 10-12 μm high, orange-brown, poorly delimited against hymenium; hymenium basally colourless or pale yellowish, gradually becoming darker in upper part, often with vertical, pale orange streaks, (35-)45-55(-65) μm high; paraphyses simple or sparingly branched and anastomosing, 0.5-1 μm thick, the apical cells apically 1-2(-2.5) μm wide, sometimes with visible gelatinous sheaths; hypothecium colourless or pale yellow, 20-75 μm high; subhymenium pale yellow, 20-25(-40) μm high. Asci 8-spored, clavate, with a K/I+ blue apical dome penetrated by a narrow, K/I- apical cushion surrounded by a narrow, deeply K/I+ blue zone, the wall K/I- but surrounded by an I+ red-brown, K/I+ blue outer layer, the ocular chamber relatively small, Biatora-type. Ascospores (0-)3(-5)-septate, hyaline, narrowly ellipsoid, (10-)12-19(-21) x (3.5-)5-6(-7) μm. Photobiont chlorococcoid. Spot tests: thallus K-, C-, KC-, P-, UV-. Chemistry: thallus without lichen substances.
Note: a boreal-montane lichen, restricted to Picea abies in the oroboreal belt of the Alps; probably more widespread but perhaps declining.
Growth form: Crustose
Substrata: bark
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly sexual

Commonnes-rarity: (info)

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

pH of the substrata:


Solar irradiation:








Altitudinal distribution:


Predictive model

Einar Timdal - Source: