dcsimg

Description

provided by The lichen genus Psora LifeDesk

Squamules: up to 5 mm wide, elongate, adnate and dispersed to adjacent or slightly imbricate, plane to weakly convex; upper surface: castaneous brown, shiny, epruinose, smooth or sparingly fissured; margin: concolorous with upper side, more or less straight, entire, crenulate or lobed; upper cortex: up to 100 μm thick, composed of rather thin-walled hyphae with round lumina, sometimes containing some crystals of lichen substances but no calcium oxalate; medulla: containing crystals of lichen substances; lower cortex: of mainly periclinally oriented hyphae, not containing calcium oxalate; lower surface: medium brown, K-; Apothecia: up to 1.5 mm diam., laminal, immarginate even when young, black, shiny, epruinose; ascospores: 10.5-13 ´ 5-6.5 μm; Pycnidia: laminal, immersed; conidia: bacilliform, 5-6 ´ 1 μm; Spot tests: upper cortex K-, C-, KC-, P-; medulla K+ red, C-, KC-, P+ orange; Secondary metabolites: norstictic acid.

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Timdal, Einar
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Timdal, Einar

Diagnostic Description

provided by The lichen genus Psora LifeDesk

The species resembles P. californica morphologically, but differs in forming somewhat smaller squamules without the often down-turned margin, in having an upper cortex composed of more thin-walled hyphae with more rounded lumina, in having pure black, more shiny apothecia, and in containing norstictic acid in the medulla. The Mediterranean-Macaronesian species P. gresinonis differs in forming smaller, more rounded and concave, olivaceous brown squamules with a slightly raised, often paler or grayish margin, and in having marginal to submarginal, smaller apothecia.

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cc-by-nc
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Timdal, Einar
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Timdal, Einar

Distribution

provided by The lichen genus Psora LifeDesk

California and Baja California del Norte.

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Timdal, Einar
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Timdal, Einar

Habitat

provided by The lichen genus Psora LifeDesk

On soil in open habitats, in Vizcaino subdivision of Sonoran Desert and in Californian coastal scrub, up to 500 m.

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cc-by-nc
copyright
Timdal, Einar
author
Timdal, Einar

Look Alikes

provided by The lichen genus Psora LifeDesk

Psora californica, Psora gresinonis.

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cc-by-nc
copyright
Timdal, Einar
author
Timdal, Einar