Lepraria jackii 

Lichen or mold? With just a casual glance, Lepraria lichens can look like mold to the untrained eye, so here is your training! Firstly, mold doesn't typically grow on healthy trees. So if you see a smear of white or green on an otherwise healthy looking tree, it is likely not mold. Secondly, if you get close, you will notice that Lepraria lichens like L. jackii are made up of fine or coarse well-delimited granules, often forming soft, random masses. Molds are typically minutely filamentous, often so small and dense that they kinda just blur together. So well delimited grains=lichens. Thirdly, lichens are a lot tougher than mold. Poke L. jackii and you will get some solid granules are your fingers, but the general structure will hold. Poke a mold, it'll fall apart and scrape right off the surface. Lastly, Leprarias and other lichens with green algal photobionts will appear darker green when moist due to the activation of their chlorophyl. Mold doesn't have chlorophyl, and so won't appear more green when moistened. So yeah, you don't have to worry if you see stuff like L. jackii on trees. Unlike molds which are saprotrophs (eat dead stuff), lichens are enclosed autotrophic systems (the photobiont makes food for itself and mycobiont) so they aren't consuming the tree or causing it any harm. In fact lichens are often an indicator of a healthy ecosystem! Hooray lichens!

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Lepraria (incana)

Lisboa/Portugal (14/02/2024)

[Nikon Coolpix P900; 50mm; 1/30s; F6,3; 200 ISO]

Lepraria or dust lichens have not been well studied in the PNW. Identification is difficult, so we almost certainly have many undescribed and unnamed species.

(со страницы centralasian :: Lepraria {Dust Lichens}; possibly Lepraria incana)

Nice collection of lichens on the venerable rocks at Indian Rock Park in Berkeley. #dustlichen #lepraria #goldspecklichen #candelariella #greenshieldlichen #flavoparmelia #sunkendisklichen #aspicilia https://www.instagram.com/p/B7JY1TkgWAC/?igshid=jqx2k1q8t7f

Lepraria lichen on puddingstone, Franklin Park, Boston

Cleric Domain of Plauge. Found primarily in followers of Pharika. Usually found in Lepraria, or Horryum.

The Physiology of Plants: or, The Phenomena and Laws of Vegetation, 1833

The root has a twofold character: it serves as the anchorage of the plant, by attaching it to the soil; the fibers, moreover, are capillary tubes, by which the plant is sustained, as they are the canals which absorb nutriment; they may therefore be considered as the tentacula of the plant. The root penetrates sometimes to an immense depth, at other times it is more superficial: its ramifications, in many instances, extend far and wide, especially in such trees as have a diffuse canopy, as in the cedar of Lebanon. In some plants, this organ appears to be entirely absent, and its functions are supplied by other means; for instance, the nostocs, or fallen-stars, palmella cruenta, or gory dew;  protococcus nivalis, or crimson snow; haematococcus sanguinens, or blood stain, and lepraria kermesina, or bloody rain, which have excited the wonder, and roused the superstitious fears and terrors of the ignorant in every age. The epiphytes, called aerial flags, or lichens, afford familiar examples of rootless plants, they are superficial, and often decorate the otherwise barren rock with varied colors, picturesque and beautiful; — all the geography of isthmus and isle; sometimes bearing also a striking resemblance to Hebrew and Chinese characters; and when rightly interpreted, it appears, some of these interesting epiphytes are legends which not only distinguish various barks from each other, and enable us to discriminate the genuine Peruvian bark, but their comparative officinal value.

Lepraria umbricola 

This crustose lichen has a powdery, leprose thallus made up of fine, green soredia growing in thin patches on acidic rock and bark. It can be found in humid microhabitats (ravines, rock crevices, old-growth forests, etc.) in warm-temperate and oceanic regions of Europe.

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Lepraria subalbicans

Lesser cottonthread lichen, almost white dust lichen

When I think of Lepraria lichens (like the rest of you frequently do, I’m sure), I picture them as a scattered mass of greenish dust on the side of a tree. Effervescent, delicate, barely looking like much at all. But L. subalbicans looks like what would happen if all that scattered dust decided to band together against an attacker an form a singular, strong, dust monster! Does that make sense? IDK I just got back from the dentist my brain is still a bit foggy. This fruticose lichen has upright, clumpy pseudopodetia that grow up to 4 mm tall, forming a dense, bumpy crust. The surface is lumpy and sorediate, and ashy-white and dull in coloration. L. subalbicans grows on soil and in rock in exposed, mountainous regions of North and South America. 

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Lepraria harrisiana

Ashes to ashes, and dust to . . . lichen, apparently. 

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Lepraria finkii

Fluffy dust lichen, spring confetti 

This lichen as a leprose thallus, meaning that it is made up of loose fungal hyphae and algal cells not covered or held together by a cortex. These gather on top of a hypothallus, so that the surface looks cottony or wooly. The margins of this lichen are more or less distinct, and can appear lobed, making it almost appear foliose. It has amore distinct margin than similar species, but can also occur more scattered and irregular, making it hard to distinguish. The coloration is bluish-green to grayish-green. L. finkii is common and widespread, and grows on bark and moss in humid regions. 

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Lepraria membranacea ( syn. Leproloma membranaceum)

Dust lichen

L.  membranacea doesn’t like to play by the rules. This lichen lacks a true cortex--the upper layer of the thallus that covers the surface. Think of it like the epidermal layer of the skin. And yeah, this lichen doesn’t have that. Instead what you are seeing is a thin membranous layer known as the medulla covered in granular soredia. This membrane forms lobes that grow in rosettes up to 3 cm wide. It kinda walks a weird line between crustose and foliose morphology. The medullary layer is white, and the soredia granules are a pale cream, yellow, or greenish. L. membranacea is wide spread, and can be found growing on sheltered rock faces and acidic tree bark all over the world. The full delimitation of this species has yet to be completely investigated using genetic information, and so this species name may cover what are actually a number of different species! Just one more way this dusty badboy is breaking the rules! 

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