Clathrus Ruber: The Basket Stinkhorn May Be the Strangest Fungus You’ll Meet

On a hike in October, about 4 kilometres beyond Vilpatti village, at the side of a narrow pathway, our small group of adults and students suddenly smelled a dead animal and looked around for a victim—only to see two of the strangest fungi. Bright red and latticed, almost cage-like, they lay just off the path we were on.

The smell of dead meat was pretty strong, and the size and colour could not be missed. They were larger than an adult fist but sitting on a greenish base, and were too interesting not to research.

This fungus, the Clathrus ruber (clathrus from Ancient Greek, meaning ‘lattice’, and ruber from Latin, meaning ‘red’), is a member of the Phallaceae family. Clathrus comprises 16 species, but only three have been recorded in India: Clathrus cancellatus (the more correct name of Clathrus ruber, as ruber is a synonym of cancellatus), C. pusillus and C. delicatus. 

All three of these species were recorded in different papers from across India: West Bengal (2012), Meghalaya (2015), Karnataka (2016) and, specifically, the Western Ghats (2019). Individual species have been recorded in other parts of India from 1996 to 2018.

The English names for C. ruber (cancellatus) are lattice stinkhorn, basket stinkhorn or red cage fungus, although it has many other names in other languages, including French, in which it is called coeur de sorciere (heart of a sorcerer). It is thought to be originally from Europe, although now is found all over the world apart from Antartica, but is a new addition to the Western Ghats and Palanis. Its arrival in foreign countries is said, in some cases, to be due to imported garden mulch containing the spores of Clathrus. However, the spores are so tiny that they could also be in the soil of plants brought in from anywhere in the world.

In 2019 studies were conducted in the Nilgiri Biosphere Reserve in Tamil Nadu by four research scholars from the Department of Botany at the KSG College of Art and Science in Coimbatore, and this was where the first official recording of C. ruber was confirmed. It was discovered at altitudes ranging from 1350 to 2042 metres and has now been confirmed as a species in the Palanis.

It was certainly the first time I had ever seen this unusual fungus, but surprisingly, when I got back to my house that day and showed my housekeeper the photos, she told me that we had one in the garden a year before, and it was found because of its smell.

Apparently it was first illustrated in 1560 by Swiss naturalist Conrad Gesner. But it was not officially described or accepted as a species until 1729 by the Italian mycologist (one who studies mushroom and fungi species) Pier Antonio Micheli in his work Nova Plantarum Genera Iuxta Tournefortii Methodum Disposita.

The fungus feeds on decaying woody plants and appears as a small greenish-white egg attached to the ground by thready cords. As it develops it splits, and the lattice appears, its inside surfaces covered in green slime. The cage-like formation comes in pink, red or orange, depending on the plant material it feeds off, and the smell of rotten meat is very strong. The tiny black spores nestle in the slime, ready to attract a variety of flies and other insects who then pass the spores on elsewhere. The main attraction for flies is the smell. 

Personally, I wouldn’t imagine many people being interested in devouring this unappetising species, but literature has reported it to have caused some ailments, although there is very little information or folklore to back this up or even declare the fungus lethal. However, in further research, I found that in parts of Europe, when the greenish-white egg-shaped fungi first develops, it is eaten as a delicacy, though it has on occasion caused a great deal of pain and sickness. This is where the entire idea becomes interesting, as the egg-like base of this species is similar to some other species of fungi in Europe and England, particularly the puffball, both the smaller and larger species. While young, small and firm it is edible, but once developed and the consistency changes, it becomes full of black poisonous spores. When young, the giant puffball, Calvatia gigantea, looks like a white egg and can grow to the size of a huge ball, sometimes as large as 3 feet across. They make for a delicious meal, tasting similar to chicken, and my mother and I used to go out hunting for the large white eggs so that we could slice them and cook them for dinner. The smaller version comes in the shape of a tiny round white egg, and is also edible, like its giant relative, until it is fully mature. Thus, the Clathrus ruber, before the lattice appears, could easily be mistaken for the puffball and eaten, although it is described as a delicacy of its own.

I’m glad to have been caught by the rather unpleasant smell of the stinkhorn and spotted it in the wild. Funnily enough, when our group found the fungi the first time, one of the students declared that he could not understand why we had stopped to marvel, as it did not, to him, smell at all, which made the rest of us laugh. A few weeks later, on another hike, we sniffed out another Clathrus in a different area, and once again were laughed at by the same student, who was sure we were making it up.

A rather similar but even more interesting species is seen in the jungles of Malaysia and Indonesia, a parasitic flowering plant that also attracts its prey with the smell of dead meat. This is the astonishingly beautiful rafflesia, usually red in colour and intimidatingly sized, with one species having the largest flowers in the world. Again, the smell is the active part of the flower, but when seen has no visible leaves, roots or stems and is attached directly to the soil. I have seen this amazing plant in an Indonesian jungle, where it was so spectacular that I just wanted to stand and gaze at it endlessly. 

This planet is currently full of the most incredible forms of flora and fauna, so it’s devastating to think that with climate change, this may not last much longer.

The story of fungi is linked all over the world by the fact that people are hesitant to try and eat them unless they are sure of what they have seen. Many species are edible but also many are very poisonous. In France some country pharmacy staff have been taught to recognise the different species and if one takes them to the shop they will tell you which ones to eat and which ones not to. I have done this several times when staying in France.

So with Clathrus ruber most people, I think, would be very hesitant to try and eat this gaudy fungi and this does also apply to the puffball especially the large one.