Welcome back to Mushroom Monday! (A day early this week to respect Remembrance Day). ‘Slime veil’ probably isn’t a phrase you expected to hear today, yet here we are. Meet Slimy Spike (Gomphidius glutinosus).
When I did my undergraduate and graduate degrees in biology decades ago, fungi didn’t get much attention. There was passing reference to their ecological roles as decomposers, and I was introduced to the lovely Earthstars while doing botanical research in sand dunes, but that was about it. Years later, I started to learn more about mushrooms and – like many beginners – was taught that Boletes have pores rather than gills under their caps. That’s often but not always the case, and there are a few families in the Bolete group that don’t play by the rules.
Slimy Spike is a member of one of those families. It’s part of the Bolete Order – on a separate branch of the evolutionary tree from most gilled mushrooms – but has gills. This is an example of convergent evolution, a bit like two people who’ve never heard of each other coming up with the same answer to a problem. There are many examples of this is nature, from unrelated plants developing the ability to produce methyl salicylate (such as Wintergreen featured in my last post) to insects, birds, and mammals developing the ability to fly.
I’ve seen Slimy Spike called ‘Hideous Gomphidius’, but I think that’s unfair. Sure, it starts out covered in a protective slime veil (yes, that’s the official term) but it’s no less attractive than any other mushroom (Photo 1). As with many cap-and-stem fungi, a look underneath is downright beautiful.
The gills are more widely spaced than those of familiar store-bought button mushrooms or their wild Agaricus relatives, and they run partway down the stem (Photo 2). On younger specimens like this one, you can see the remnants of the slime veil which stretches and breaks apart as the mushroom grows. Caps of older specimens remain slimy like Slippery Jacks (Suillus spp.), a related family within the Bolete Order. A look inside Slimy Spike reveals white flesh at the top becoming bright yellow at the bottom (Photo 3).
Slimy Spike is associated with conifers, and I found these under old field White Spruce in Central PEI. It was originally thought to be mycorrhizal with species such as Fir, Pine, and Spruce, providing the trees with water and nutrients in exchange for sugars they make via photosynthesis. More recently, evidence suggests Slimy Spike is parasitic on other Boletes that do form relationships with trees, tapping into this network to steal some of the nutrition for itself.
There aren’t many reports of Slimy Spike on PEI, but it may just be overlooked as so many of our fungi are. A similar-looking relative – Rosy Slime Spike (Gomphidius subroseus) – is also known from the Maritimes but hasn’t yet been confirmed on the Island.
Slimy Spike is an edible mushroom, but there are two reasons I didn’t take one for the team and try it. First, I didn’t know it was edible when I found it and so didn’t collect any. Second, that slime veil looks decidedly unappetizing (though it is removed before cooking) and just didn’t inspire me to go back and get some. If I pass it again, I might give it a try, but I can live without tasting this slimy part of PEI untamed.
Comments