Chlorociboria

January 1, 2025

Chlorociiiiiibooooorriiiiaaaaa!

I realized I haven’t posted a fungal friend in awhile, and that’s just not on. Because I have so mushroom in my heart for these little pals!

This magical tiny beauty is blue-stain fungus, also known as green elfcup or wood cup. How tiny? The second photo has my human-sized hand for scale.

Its scientific name is Chlorociboria aeruginascens (or aeruginosa, a very similar species that you can only tell apart with a microscope). It’s a good example of why scientific names are so cool, because they often tell you something about the plant or animal you’re observing. In this case, “aerug-“ means “blue-green” (aerugo = verdigris/patina) and “ascens” means “becoming”.*

*NB this fact-based naming is less true of some more whimsical scientific names. Such as the puffball mushroom Lycoperdon, which means… Wolf farts. 🐺💨

I first met blue-stain fungus in our woods not like it looks here, with its tiny teal cups, but like it looks most of the time – as if someone had spray-painted a fallen log with greenish paint. Of course I got all mad about the spray paint thing, because I can be a hot-headed little red squirrel. Only later did I learn it wasn’t a human who had tagged the tree, but nature. Whoops. Easy there squirrely girly 🐿️

While the spray-painted look is persistent – so persistent that wood with Chlorociboria was historically used in decorative woodworking – it’s only after a solid stretch of wet weather that the little cups suddenly show up. Like today, when I spotted these luscious lovelies while out for a run. Their appearance is always a reassuring sign that long dry days and fears of drought have passed for now, and it’s time instead to fill your soul with these itty bitty cups and the relief of a good long rain. 💙🍄