Yes, we’re back, and there’s news in the world of lichens. Please forgive the long “dormancy,” of which more is explained below. But right now, things are popping in the world of lichens, and we thought we’d better attempt to update ourselves just a tad.
The Overlooked Organisms That Keep Challenging Our Assumptions About Life, at The Atlantic. As they say, “Gorgeous and weird, lichens have pushed the boundaries of our understanding of nature—and our way of studying it.” (by Ed Yong Jan 17, 2019)
[Or maybe not so “latest” after all. Here’s an earlier article about the researcher who put this idea together, Toby Spribille, also by Ed Yong, in the Atlantic in 2016.]
We’ve talked before about the fact that some lichens contain multitudes—specifically, representatives of not just two but THREE kingdoms within their symbiosis. Now, researchers are demonstrating that the situation for some lichens may be even more complex.
Hooray for lichens—the organisms that continually surprise us!
Lichen-forming fungi [all*] belong to a group called the ascomycetes. But in 2016, Spribille and his colleague Veera Tuovinen, of Uppsala University, found that the largest and most species-rich group of lichens harbored a second fungus, from a very different group called Cyphobasidium. (For simplicity, I’ll call the two fungi ascos and cyphos).Look on the bark of conifers in the Pacific Northwest, and you will quickly spot wolf lichens—tennis-ball green and highly branched, like some discarded alien nervous system. When Tuovinen looked at these under a microscope, she found a group of fungal cells that were neither ascos nor cyphos. The lichens’ DNA told a similar story: There were fungal genes that didn’t belong to either of the two expected groups. Wolf lichens, it turns out, contain yet another fungus, known as Tremella. —Ed Yong
* There are, as I understand it, a few lichen-forming Basidiomycetes as well. But for practical purposes… ascomycetes.Tremella is commonly known to us ordinary mortals as “witches’ butter” and is a parasitic jelly fungus that seems to be fairly distinctive. I posted this photo on iNaturalist, however, and haven’t had anyone confirm its identity to date.
Tremella fungi had been reported from wolf lichens previously, but were thought to be “secondary” to the main symbiotic relationship. The “news” here is that these extra fungi may, in fact, be quite central to the concept we call lichens. At least in the genus Letharia. We’ll be staying tuned to new developments!
Yes, I’ve recently been getting active on iNaturalist (@slwhiteco), and am especially intrigued by checking out the lichens there. Unfortunately for me, lichen taxonomy has changed significantly since I studied them back in the Darkish Ages. Apparently the advent of DNA analysis has stimulated, or required, major revisions in groups, and I’m still trying to untangle the implications. Perhaps we’ll explore a few of them in a future post.
My other complicating factor is that I’m no longer in Colorado. The move, and preparations for it, were a significant distraction from this website, but we’ll hope to bring you more lichen material in the future. Sadly, other than several Cladonia and some corticolous species, I’ve not found good lichen-hunting in this part of upstate New York yet.