The Devil's Bolete

The Devil's Bolete Rubroboletus satanas (Fr. Bolet Satan) is a mushroom species related to that delicious and well known delicacy the cep (or as you might know it by its Italian name, porcini). Toxic and rather rare, the scary name is well known to foragers, but they can't necessarily correctly identify it when they find it. It is quite distinctive looking though, with a white cap, bulbous red stem, red spongey pores and if you cut it a sky blue stain emerges. Nothing else has that combination of characteristics, but it is true that there are a dozen or so species that do look superficially like the Devil's Bolete.

I spotted one in the Forest of Preuilly the other day and thought I'd snaffle it to take photos for my archive and for the blog and social media. It was not far off the track, partially hidden by fallen leaves. To be honest, it looked like a piece of limestone rock. But there was something about it which made me go over and take a look. As soon as I saw the red stem I knew what it was. The local fungi foraging group on Facebook is showing that a couple of other people have found them in the last few days too, in the Forest of Loches.

It's one of the relatively few toxic boletes or ceps, so that combined with its striking appearance and rarity has turned it into rather a legendary species. In some areas of France it has been Red Listed as Near Threatened.

There are several red pored boletes, and studies show that although they belong to the Boletaceae family, they are not all that closely related to 'true' ceps. Those red pores and the blue staining when cut are what distinguish the relatively new designation of the genus Rubroboletus.

As well as being well known for its toxicity, the Devil's Bolete is also the largest recorded bolete in France, and can grow a cap up to 30 cm in diameter. The one I found was a modest tennis ball sized specimen, much more typical in my experience. With age the cap tends to flatten out, and go greyish. If there is any sign of pink on the cap it almost certainly means it is another closely related species and not a Devil's Bolete.

Underneath the cap there are yellowish tubes (only visible if you cut the mushroom), ending in fine red pores so that it is like a sponge. The stem (called a stipe) resembles a large radish in both shape and colour. When you cut the mushroom you can see that the flesh is whitish, and slowly turns sky blue on exposure to the air. Take a good sniff and the mushroom smells unpleasantly of slightly off meat.

The Devil's Bolete likes warm calcareous habitat where it grows under beech, oak and hornbeam. It appears at the end of summer or the beginning of autumn in response to hot stormy weather.

Despite its name the Devil's Bolete isn't really dangerous to a healthy adult. Consuming it will cause nausea, repeated vomiting, and diarrhoea, sometimes with traces of blood. Poisonings are very rare though because the appearance and smell of the mushroom does not encourage one to eat it.

Although the name Devil's Bolete is well known amongst foragers it is not always applied to the correct species. There is a tendency to call any red pored bolete that turns blue when cut a Devil's Bolete.

One of the common lookalike species that is often passed over 'just in case' is the Scarletina Bolete Neoboletus luridiformus. See this blog post for a photo https://daysontheclaise.blogspot.com/2023/10/fungi-foray-at-carrefour-de-linspecteur.html