A frog in India with a fungus coming out of it. Researchers have never seen anything like this before

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When observing a hoard of golden-backed frogs in a roadside pond in Karnataka state, India, a group of naturalists noticed something strange about one of the amphibians — the animal had a small fungus sprouting from its side.

How the seemingly healthy frog managed to grow its inbred mate — an event that had never before been documented — has left scientists scratching their heads, according to a paper published in January in the journal. Reptiles and amphibians.

“When I first saw the frog with the mushroom, I was amazed and mesmerized by the sight,” Lohit Y. T., a river and wetland specialist at WWF India in Bengaluru, said via email. YT was part of the group that discovered the frog. “I thought about documenting it, as this is a phenomenon we have never heard of before. We just wanted this to be a rare occurrence and not a dangerous phenomenon for the frog.

Species – known as Rao's intermediate golden-backed frog, or scientific name: Hylarana intermedia – It is found in abundance in the states of Karnataka and Kerala in southwestern India. Frogs are small, reaching only 2.9 inches (7.4 cm) in length.

As naturalists watched the frog as the fungus grew, the animal moved from the center of the branch it was sitting on to the tip, turned and changed position, but the fungus remained exactly where it was, YT said. The group did not touch the frog.

The authors discovered the amphibians in June 2023 and did not collect them, so neither the cause of the phenomenon nor the fate of the frog is known.

But through photographs, mycologists later determined that the fungus growing from the frog's flank was a fungus Common hoodIt is part of the Mycena genus, a type of fungus that grows mostly on rotting wood from dead trees, the authors wrote in the published paper. Mushroom is Rime analysta fungus that usually obtains its nutrients from dead or decaying organic matter – but a Study 2023 She found that fungi can evolve to thrive on living plants as well.

The 2023 study also suggested that mycena fungi could evolve to have a symbiotic relationship with living plants or trees, meaning that both the plant and the fungi growing on it would benefit from the arrangement — the fungi would take nutrients from them and transfer them to the plant host. The researchers added that mycenae can be beneficial in trees by pruning dead branches.

The prognosis of the toad with innate traveler is unknown, but there are a few theories about the cause of its condition.

When first seeing the report of the frog with a fungus attached to its wing, Alyssa Wetterau-Kaganer, a postdoctoral fellow in the Department of Public and Environmental Health at Cornell University College of Veterinary MedicineI found the discovery fascinating.

“Fungals are dynamic organisms that adapt to changes in their environment, and with exposure to new potential hosts in different environments or climates, they may grow in places we never expected before,” she said in an email.

While it is difficult to predict a frog's fate without further study of its condition, it is possible that “a healthy frog can tolerate mild colonization of its skin by this fungus without any adverse health effects,” Caganer said. She added that fungal infections in frogs are very common, and if the fungus grows extensively on the skin or burrows inside the animal's body, the animal may develop signs of a fungal disease. Kaganer was not involved in this discovery.

There are many types of fungi that can infect frogs, and it is possible that there are interactions between fungi and frogs that have not yet been discovered. A frog that shows signs of a fungal disease, such as “changed frog behavior” or “skin damage including ulceration or tumor-like nodules,” is suffering from an infection that can often lead to the death of at least some of the infected animals, Caganer said. .

Anything out of the ordinary, including fungal growths like this, is a concern for the frog species, he said Karthikeyan Vasudevan, senior scientist at the Endangered Species Conservation Laboratory at the Center for Cellular and Molecular Biology in Telangana, India. Vasudevan was not involved in the discovery and was also surprised by the discovery.

“Sick animals in the wild have very little chance of survival. It is difficult to notice a sick animal, because it dies or is eaten quickly. So something like this is interesting and should be followed up by observing and examining the frogs,” Vasudevan said in an email.

At first, Vasudevan thought the fungus was stuck on the frog's skin rather than a growth, but photos of the frog convinced him otherwise. “It's really a case of a live fungus on a live frog,” Vasudevan said. “But one possibility is that there was a small piece of woody debris under the frog's skin after it became lodged in the skin and a fungus sprouted from it.”

India is currently facing an epidemic of a frog-killing disease known as chytridiomycosis, a fungal infection that affects more than 700 amphibian species worldwide. The authors of the new note wrote that the disease has been observed at low levels in all frog hotspots across India.

Chytriid disease is an example of a common interaction between amphibians and fungi. The authors don't know if it's related to this finding, YT said.

“This particular type of fungus is not closely related to the types of fungi that cause chetriomycosis, so I'm not concerned that this fungus is a direct sign of chetriomycosis,” said Kaganer, who studies the disease. “However, it is possible that a frog infected with Mycena has altered susceptibility to fungal infection.”

She added that a frog carrying the fungus on its side either has an increased susceptibility to chytriomycosis from exposure to mycoplasma, or it could be more immune “because mycobacteria has pushed the frog's immune system into high gear.”

“We have no hope of going after the frog, because this is not a common phenomenon,” YT said. He added that the authors will visit the site again during the next monsoon season, when the weather is warm and rainy and frogs are more abundant.

“If we can find him, it would be great,” YT said. “This place is frequented by many enthusiasts and experts alike. It would be great if some researchers could get their hands on it and be able to further investigate, but again, it's unlikely that will happen.”