#lichens

[lichenaday]

Punctelia graminicola

I love learning about a member of a familiar genus I have yet to meet! P. graminicola grows on rocks, moss, and occasionally bark or burned wood at low elevations in North America down in South America. This foliose lichen has a wide, adnate to loosely attached thallus of narrow, sublinear lobes that are pale blue-gray to green-gray on the upper surface, and pale tan on the lower surface. As with other members of the genus, it has point-like or pore-like pseudoceyphellae (openings in the outer layer of the thallus to the inner medullary layer). What's really cool is that scientists actually studied the developmental physiology of these structures within the genus, and found that P. graminicola forms these structures by arranging the medullary hyphae in circular groups and pushing from the inner layer out, shoving the algal layer up, eventually bursting through the cortex, leaving a gaping hole into the lichen!

Ok maybe not "gaping" per se--they are really small. Why does it go through all this effort to form these pores? The prevailing theory is gas exchange for the photobiont layer during photosynthesis, but that likely is only part of the story, as not all lichens have pseudoceyphellae but all perform photosynthesis.

images: source | source

info: source | source

[lichenaday]

Pertusaria texana

Texas wart lichen

She ain't perty, but she's got an awful sweet spirit. P. texana is a crustose lichen that grows on smooth-barked trees in Mexico and the southern United States, as well as the Galapagos islands, Australia, the Seychelles, and Papua New Guinea. It has a wrinkled and bumpy, pale yellow-green thallus that glows orange-red under UV light due to its production of thiophaninic acid. It produces apothecia deeply embedded in conical thalline warts, which are often topped by "yellow nipples" at the openings (their words, not mine). Ah, that explains why this post was under content label review for so long. I have stared at lichens for so long that they all just look like lichens to me, not these human anatomy features y'all see. At this point I am more likely to see a person with their shirt off and be like "what interesting lichens you have there!" than the other way around. TMI?

images: source | source

info: source | source | source

[wiley-treehouse-gardens]

South Africa, 2025

[lichenaday]

Dibaeis absoluta

OK, so why does this lichen look like it is growing mushrooms, even though these are decidedly not mushrooms? My first answer is "just to fuck with you," but D. absoluta evolved long before humankind, nonetheless you specifically. So my second answer is because the mushroom shape just makes functional sense when you want to produce a fruiting body by maximizing the physical area that produces spores, and raising them above the substrate by a thin stalk so they can get caught in and distributed by wind. Ok, so they are the spore producing structure of fungi, shaped like that, how are they not mushrooms? Mushrooms are we typically think of them are the reproductive structures of basidiomycete fungi, the spores are typically released from the lower surface of the fruiting bodies like this:

And in an ascocarp, the reproductive structure of an ascomycete fungi like that of D. absoluta, the spores are released from the upper surface of the fruiting bodies. So like this:

OK this is waaayyy simplified. There are also a bunch of internal physiological differences but you, dear reader, can look those up yourself if you are curious about the nuances of fungal development. But very generally speaking, basidiospores come out the bottom, ascospores come out the top.

So not tiny mushrooms, but very very cute just as they are!

images: source

[lichenaday]

yesterday a visiting undergrad came into my work and was telling me about how she's doing her undergrad research project about lichens even though no one at her university studies or even knows very much about them. heartwarming to know that there are young people choosing the lichen lifestyle even though it is a difficult and often lonely road 🔥💪💯💵

Making it happen (lichens) in the face of adversity (no lichens). That's the kind of badassery I like to hear about! Praying to the lichen gods on her behalf that the lichen life treats her kindly and all of her dreams come true.

[lichenaday]

I llove following both you and several insect blogs because I'll be scrolling on my dash and see a picture of lichen and for a few seconds I go "am I looking for a camouflaged bug or is it pure lichen" and its a blast every time

I wasn't aware they let birds have tumblr accounts . . .

[lichenaday]

Lecidea perlatolica

images: source