Lecidea diducens Nyl.

Flora, 48: 148, 1865.
Synonyms: Lecidea auriculata var. diducens (Nyl.) Th. Fr.; Lecidea auriculata var. subfoederata Vain.; Lecidea sarcogyniza Nyl.
Distribution: N - TAA (Hertel 2001, Hertel & Schuhwerk 2010), Lomb (S-F86838), Piem (Isocrono & al. 2004), VA (Piervittori & Isocrono 1999), Lig.
Description: Thallus crustose, endosubstratic or very thinly episubstratic and grey-white, without a distinct prothallus. Medulla I+ intensively violet-blue (but usually very thin and reaction difficult to observe). Apothecia lecideine, black, sessile and constricted at base, round o rirregular in outline, sometimes confluent, 1-2.5 mm across, with a flat, mostly epruinose disc, and a prominent, rather thick, persistent proper margin. Proper exciple of intricate-radiating hyphae, 100-130 µm wide laterally, extending below the hypothecium, dark brown to violet-brown in outer part, paler within, C+ red, inspersed with small crystals; epithecium olive-black, blue-green or blue-black; hymenium colourless, 34-50 µm high; paraphyses coherent, mostly simple, 2-2.5 µm thick at mid-level, the apical cells 3.5-4 µm wide; hypothecium pale brown to black-brown, with a thick medulla. Asci 8-spored, narrowly clavate, thick-walled, with a K/I+ pale blue tholus and a strongly amyloid, thin apical cushion, surrounded by a I+ blue outer layer, Lecidea-type. Ascospores 1-celled, hyaline, narrowly ellipsoid with obtuse ends, (6.5-)7-11(-12) x 2-3.4 µm, 2.5-4.1 times as long as wide. Photobiont chlorococcoid. Spot tests: thallus and medulla K-, C-, KC-, P-. Chemistry: 2'-0-methylanziaic acid in apothecia, confluentic acid in thallus.
Note: a circum- and bipolar, arctic-alpine silicicolous lichen (Hertel 2006), ecologically similar to, and closely related with L. auriculata.
Growth form: Crustose
Substrata: rocks
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly sexual

Commonnes-rarity: (info)

Alpine belt: rather rare
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
Herbarium samples

Einar Timdal - Source: http://nhm2.uio.no/lav/web/index.html - CC BY-NC

Curtis Randall Björk – CC BY-SA 4.0
Northwest Territories, near MacKay Lake Date: 2011-08-00 On pebble, gravelly, windblown ridgetop in brushy tundra


Culberson, CF/ Hertel, H (1972) 2'-O-Methylanziaic acid, a new depside in Lecidea diducens and Lecidea speirodes. The Bryologist

Hertel, H (1997) On the genus Lecidea (Lecanorales) in southern Chile and Argentina. Lichen Studies Dedicated to Rolf Santesson

Zhang, L.-L./ L.-S. Wang/ H.-Y. Wang/ Z.-T. Zhao (2012) Four new records of lecideoid lichens from China. Mycotaxon