Lepra borealis (Erichsen) I. Schmitt, B.P. Hodk. & Lumbsch
in Wei & al., PLoS One 12, 7: 7, 2017. Basionym: Pertusaria borealis Erichsen - Ann. Mycol., 36, 4: 354, 1938
Synonyms:
Distribution:
Description: Thallus crustose, episubstratic or rarely endosubstratic, pale grey to pale grey-green, continuous to often rimose, even to distinctly tuberculate, sometimes delimited by a thin whitish prothallus, forming up to several dm wide patches, with mostly discrete (rarely confluent), rounded, convex, rarely excavate, up to 1.5(-3) mm wide, white, pale green-grey, blue-green or yellowish white soralia bearing up to 80 μm wide soredia which are often gathered into up to 0.2 mm wide consoredia. Apothecia rare, developing within soralia, disciform, with a pale pink, up to c. 0.7 mm wide, more or less white-pruinose disc. Hymenium colourless, c. 120 µm high; hypothecium colourless. Asci 6-spored, broadly cylindrical, the apex without a distinct ocular chamber, the outer sheath K/I+ blue, otherwise K/I–, with an inner extensible layer, Pertusaria-type. Ascospores 1-celled, hyaline, broadly ellipsoid, 18-20 x 10-14 µm. Pycnidia rare, immersed, pale pink. Conidia narrowly fusiform to rod-shaped, 5-7.5 x 1 μm. Photobiont chlorococcoid. Spot tests: thallus K+ yellowish turning brownish, C-, KC-, P+ orange-red, UV- or UV+ faintly blue. Chemistry: fumarprotocetraric, protocetraric and succinprotocetraric (trace) acids. Note: based on a type from Alaska (the asci of Alaskan fertile specimens were reported as 1-spored!), and also known from NW Europe on the bark of deciduous trees, more rarely of conifers; in the Alps there are so far only a few records (Austria, Switzerland) from old-growth forests under suboceanic climatic conditions. To be looked for in Italy.
Growth form: Crustose
Substrata: bark
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly asexual, by soredia, or soredia-like structures (e.g. blastidia)
Most common in areas with a humid-warm climate (e.g. most of Tyrrenian Italy)
Predictive model
Curtis Randall Björk CC BY-SA 4.0
British Columbia, Glacier National Park. On decorticated twig of conifer in rain forest
August 2005
Curtis Randall Björk – CC BY-SA 4.0
British Columbia, Glacier National Park Date: August, 2005 On decorticated twig of conifer in rain forest
Growth form: Crustose
Substrata: bark
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly asexual, by soredia, or soredia-like structures (e.g. blastidia)
Most common in areas with a humid-warm climate (e.g. most of Tyrrenian Italy)
Predictive model
Curtis Randall Björk CC BY-SA 4.0
British Columbia, Glacier National Park. On decorticated twig of conifer in rain forest
August 2005
