#micarea

Micarea prasina

Green dot lichen

This is a very difficult species to describe faithfully, as it was recently split into over 20 cryptic species! So I am trying to use the most up-to-date info on M. prasina s. str., but who knows, man. This crustose lichen has a bright to dark green thallus made up of dense aggregations of rounded granules (goniocysts), sometimes coalescing to form isidioid structures. It is often sterile (one of the many features that makes this guy difficult to ID), but can produce bulbous apothecia which vary in color from white to gray to brown to black. M. prasina presumably grows on dead wood and tree bases in old growth forests, but more work is needed to separate out its range and habitat preferences from the newly described species.

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Might I offer you something small from a nearby oak wood? I think this is Micarea stipitata, a lichen which grows on bark in amongst mosses and liverworts. It has upright, stalked pycnidia and low, rounded apothecia; both are translucent and rather beautiful. It is, however, a bit too small to be easily appreciated.

A recent trip to Red River Gorge has supposedly led to some interesting findings, or rather a potential accident of some kind. I posted this lichen image on I naturalist to see what it was as I was very unfamiliar with anything that could compete or mat this aggressively to the point that even moss was having a hard time establishing past it. My friend Shaun managed to correct my attempt at Identification and he seems pretty sure about the ID all though im waiting on two others to comment on it as Ide prefer curators in something like this.

Due to recent storm damage and downed trees it has now become an optimum time to look at dry bark before rot starts phasing in and humidity invites more fungus and moss not associated high light exposure and upper canopy of trees in the gorge, it also luckily has caused unofficial trail hikers to learn to meander or create new trails via bushwack and elephant path(desirepaths) in order to relocate the original unofficial trails since trail maintenance only exsists for those that are declared official trails. During one such meander I accidentally walked past this lichen for the first time in my life.

Micareopsis irriguata

Sandstone Sea fog/foam lichen.

A species only mentioned in the Keys that I have but has no photos available due to it's scarcity, it has 1 report in Kentucky besides this current one in Red River Gorge and has plenty of potential to be found in many locations where sandstone ravines are found (WV, KY, TN, IL, IN, OH, PN, AL.) Yet reports are minimal and records are scarce in herbariums. Right now for example I nat has less than 20 reports on the species as a total.

Surrounded by some moss, Cystocoleus ebeneus (black hair lichen); There are actually other lichens in this shot too that are not easily identifiable and what may be Leptogium spp. of some kind and or Scytinium spp. or perhaps some mealybug like look alike maybe even a pin lichen. Found on a humid exposed sandstone cliffs near the base of cliff face, Bison Way downsend trail near the upsend roots to Adena Arch shortcut.

Sea foams and rain forest lichens are very similar and are common names for a group of species associated with a bullate(thick bumpy, often with convex tile-like areoles) thallus that is somewhat reminiscent of foamy surfaces. These aren't necessarily uncommon nor rare in rocky areas but some are definitely less present due to inland association or coastal association and microclimates. This was more of a happy accident to me, I was curious about it, hadnt noticed it in the area before, didn't know what it was at all, so I took a picture to look it up as it was way more dense than a powder lichen (like Lepraria finkii or Botryoleparia lesdainii and had apothecia instead of what I associate with almost ascoma like reproductive structures that are often seen on things like the mucose thalloid mats of Multiclavula mucida and thicker crustose hard algal like thalloid mats like those associated with Dibaeis spp, or perhaps Bacidinia delicata and Baeomyces rufus. Similarly it is notable that im not the only one who associates these species at all because we can juxtapose the name sake of Micareopsis spp., which could of used oides as well to mean "looks like", to Micarea spp.

Micarea lignaria

She's never had to apply for a visa, or fill out seemingly endless amounts of paperwork. An email has never found her. She doesn't know who Elon Musk is. Love that for her. This crustose lichen grows in humid locations on moss, humus, lignum, dead wood, and acidic rock. It has a granular, pale green to olive, crustose thallus, and globose, black apothecia. Micarea lignaria comes in 2 flavors: M. lignaria var. lignaria, which is more common, and M. lignaria var. endoleuca, which is chemically different and more restricted in its range. You can tell the 2 apart using a bleach spot test on the thallus (endoleuca turns orange).

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Micarea incrassata

I am currently bird ringing and lichen sampling in Iceland, and just got the beloved/hated question, "So what do lichens *do*?" Beloved because it's an invitation to info dump about lichens, but hated because it implies that lichens are kinds useless and don't serve an obvious function. And in a place like Iceland, this particularly drives me nuts. You see, Iceland is geologically very young, and is made up of volcanic rock. And on top of that there's the cold, and the rain, and the WIND. And this means that the soil is very inorganic and not ideally suited to plant growth, and subject to a vicious cycle of erosion (plants can't establish on constantly eroding soil and the soil erodes because there is nothing anchoring it. And this is where lichens come it! We often think about lichens growing on trees and rocks, but plenty of lichens lichen M. incrassata specialize in growing on soil (terricolous), forming a crust that helps to stabilize the soil, reduce erosion, and creating a more ideal habitat for plants and other organisms! I find it ALL over Iceland, including on my little seaside walk today here in Höfn.

Also interesting to note that M. incrassate is a tripartite lichen, meaning that it has both green algal and a cyanobacterial photobionts (housed in those brownish cephalodia patches). Soil holding is just one of MANY ecosystem services provided by lichens here in Iceland and around the world. Just because they are small doesn't mean they aren't important!

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Micarea leprosula 

When the students in our lab group doing lichen ID come to me and ask me hos to ID crustose, sterile (not producing fruiting bodies like apothecia) lichens, I can only laugh manically and wish them the best of luck. Characteristics of the fruiting bodies (color, size, number of spores they produce, etc.) are some of the best, and often only features to differentiate small, crustose lichens. When they don't have those, you often have to go off of characters that are a bit more variable and difficult to distinguish. Because of this, lichens like M. leprosula that don't often produce apothecia are likely overlooked throughout the full extent of their range. For now it is known only from Europe, but who know where else it might be found, and specimens of it are just sitting in collection boxes somewhere, unidentified by the poor students working on ID projects who don't have the knowledge, time, or patience to figure them out. Wait am I part of the problem? BRB, gonna go give these students a pep talk and apologize for the villain laugh earlier . . .

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Micarea denigrata

Micarea hedlundii

Hey, it's not polite to stare. I know this lichen has its pycnidia all out there in the open like that, but c'mon, show a little decorum. Just kidding, stare all you want. That's the point of this blog. Gaze upon the little weirdo that is M. hedlundii. This crustose lichen has a thallus of granular goniocysts (algal colonies inside a fugal sheath) which are dull olive-green on the outside, oily yellow-orange to violet on the inside. It only rarely produces apothecia, which are small and grayish brown to dark brown in color. Its most noticeable feature are those stalked pycnidia. What are pycnidia? They are flask-shaped, asexual reproductive structures which produce vegetative propagules. In most lichens, they are embedded in the thallus and inconspicuous, but M. hedlundii decided to make them a feature. These pycnidia are cylindrical, pink-brown to gray brown in color, and covered in white tomentum. Why? Because why not, I guess! If you want to stare at this gorgeous little weirdy in real life, you can find it growing vertically on stumps and rotting conifer wood at high elevations in scattered arctic-alpine regions of Asia, North America, and Europe.

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