I’d like us to all think for a little bit about the way that we apply names to organisms around us.
I started thinking about this after my friend Danny Newman hijacked the comments thread on this Mushroom Observer post of a Xylaria from Portugal. This post, but the amicable and cryptically-named zaca, was of a cute little Xylaria growing on a mossy log in a park in Lisbon. They’d tagged the find as “Xylaria polymorpha“, one of the two names for species of Xylaria often included in field guides; the other, of course, is “Xylaria hypoxylon“. Danny used the application of this widely misapplied name in such circumstances to start a more general conversation about how we apply names to fungi. I’d encourage you all to go read that comment thread, if you haven’t already.
One thing that comes out of that conversation for me is some thought about the culture around identification. People like to categorize things — it has been theorized to be a universal human trait. It is no different for mycologists, particularly amateur mycologists. We want a name for the things we see; to many people, to name something is to know it, to understand it. We want to figure out what a mushroom is, to put it in the box of a species, because that satisfies some obscure desire to classify and categorize the world around us. This potentially is the same process of thought that leads to unconscious racism and sexism in some people.
I realized that I have contributed to this culture in the past by providing names (and with some perceived authority, too!) in situations where really I should be saying “it isn’t possible to confidently identify this fungus without more information” or the like. I have since started to make an effort to alter the culture around identification by saying firmly when there is not enough information to apply a name, but the biggest thing we can do is to help people feel comfortable with putting things in bigger boxes — zaca’s Xylaria is still in the bigger box of genus, with no epithet applied, because without a specimen there is no way to confidently pin an identification to that observation. (Though there is a probable identification at the species level — Xylaria cf. cinerea — so I suppose we can say it’s in a hard genus box, and a soft species box. Or maybe a “c(o)f.(t)” species box?)
Part of changing this culture around identification will be in the way we approach writing guidebooks. Part of why zaca initially named their specimen “Xylaria polymorpha” was the guide they used to identify it. David Arora’s tome, Mushrooms Demystified, only keys two species of Xylaria (X. hypoxylon and X. polymorpha), noting two more in the comments on these species (X. cornu-damae and X. longipes), but only to say “there are many Xylarias [sic] that more or less resemble this species … but they are best differentiated microscopically.” He gives no information on how to differentiate them microscopically, though. Even Mike Beug’s new Ascomycete Fungi of North America only lists a few species of Xylaria.
We have these keys that lead to distinct species, rather than genera, or groups of species, or whatever broader division, because people like to be able to pin a name on what they find. That’s the cultural issue. But there’s a feedback loop between that culture and the way guidebooks are written — the guidebooks reflect the culture, but they also perpetuate it. When we write guidebooks or online keys or the like, we should be making sure that they are clear about their limits, and they should work to normalize the use of broader boxes. Given the field guides and keys available, of course people put these names on things — what else can they do!?
What’s needed is a cultural shift to being okay with genus, or even higher order, identifications, and an understanding that (particularly for ascomycetes) the guidebooks are far from all inclusive. And I think those are lessons that people are ready and willing to learn, if we are willing to teach respectfully. Take this particular observation as an example: zaca was perfectly willing to accept a genus-level determination after understanding what was going on (and willing to dig into the diversity question deeper), but until someone explained, how were they suppose to know what was wrong with the name X. polymorpha? It’s what the guidebook said, after all!
The other thing that we need, of course, is more detailed, publicly accessible guides to particular groups of fungi, my grinding-stone being, of course, a relatively comprehensive guide to the Xylaria of the world: there are more than 800 described species in the genus, and no place with more than a few dozen in any single key. And when it’s time for me to write a lay-person’s guide (and that time is coming), I plan to make the limits of that key very clear. Who’s with me?