ITALIC 8.0

Verrucaria obfuscans Nyl.

Flora, 64, 34: 540, 1881.

Synonyms: Amphoridium deminutum (Servít) Servít; Amphoridium impurum J. Nowak

Distribution:

Description: Thallus crustose, episubstratic, 0.3-1.2 mm thick, areolate, the areoles angular, 0.5-1.2(-2) mm wide, flat or slightly concave, separated by deep cracks, pale to medium brown, the flanks concolorous with the upper surface or slightly darker, the upper surface subdivided by inconspicuous thin lines. Cortex consisting of a single layer of small cells with a dilute brown pigment, covered by an epinecral layer; algal layer interrupted by brown-pigmented medullary areas, the cells arranged in weak columns; medulla forming a brown basal layer. Perithecia black, mainly 1/4 to 1/2 (rarely 3/4) immersed, forming 0.1-0.2 mm wide projections. Involucrellum absent; exciple 180-250 µm across, the wall pale brown to brown throughout; hamathecium of 20-25 µm long periphysoids, interascal filaments absent; hymenial gel hemiamyloid, I+ red (I+ blue at very low concentrations of I), K/I+ blue. Asci 8-spored, clavate, I-, fissitunicate, the wall thickened above, with an ocular chamber, dehiscent by extrusion of an endotunica to form a delicate rostrum, Verrucaria-type, 50-75 x (15-)20-25 µm. Ascospores 1-celled (rarely a few 1-septate), hyaline, narrowly ellipsoid, 16-22 x 7-8 μm. Photobiont chlorococcoid. Spot tests: K-, C-, KC-, P-, UV-. Chemistry: without lichen substances.

Note: a calcicolous species apparently belonging to the V. nigrescens-group, based on a type from Paris in France, growing; on walls and other anthropogenic, sometimes metal-enriched substrates at low elevations; rarely recorded because not always distinguished, known from a few localities in the Alps. For further information see Breuss (2007), Breuss & Berger (2010), Krzewicka (2012) and Orange & al. (2023). To be looked for in Italy.

Poorly known taxon in need of further study

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Predictive model

Source: https://fungi.myspecies.info/sites/fungi.myspecies.info/files/Verrucaria%20obfuscans2.jpg - Photo uploaed by Mark Powell -CC BY NC

Verrucaria obfuscans, thallus composed of rounded algal units (most units containing a single perithecium) agglomerated into areoles separated by cracks. Growing on iron-stained limestone windowsill of church, Oxfordshire.

Source: Servit, M 1949: Nove nebo mene zname druhy lisejnikove celedi Verrucariaceae. Species Verrucariacearum (Lichenes) novae vel minus cognitae. - Sbornik Narodniho Musea v Praze 5(9): 1-51. Tab.3 - Public Domain

Source: Servít M. 1954a. Lichenes familiae Verrucariacearum. Prag, 249 pp.

as Amphoridium obfuscans