Big Hainan mushroom draws public attention

A science popularization article published on May 28 on the cantharellus macrocarpus mushroom, the king of cantharellus in South China's Hainan province, has drawn the attention of the Chinese bioscience community, and even the public.

"The article aims to introduce the distinctive species. I think it's the cantharellus macrocarpus' abnormal size and upbringing that has aroused readers' interest," said Zeng Niankai, a professor at the School of Life Sciences of Hainan Normal University who discovered the mushroom.

The cantharellus macrocarpus only grows in Hainan Tropical Rainforest National Park. With a cap diameter of up to 16 cm, it is the largest individual among the species of cantharellus, more commonly known as chanterelles, found in the province.

"The cantharellus is not rare in the park, but the cantharellus macrocarpus is unusual in its size," said Qi Xuming, director of the Education and Publicity Division of the Bawangling branch of the national park.

Zeng found the giant mushroom on May 23, 2019.

That day, he took his graduate students to the Bawangling area of the national park to conduct investigations and discovered it.

"We didn't look for it on purpose, but found it during a routine investigation," Zeng said.

The cap diameter of an ordinary chanterelle is about 5 to 6 cm, or even smaller, but that of the newly discovered can reach 16 cm. The flesh of the mushroom is white and doesn't change color even if injured. The surface of its hymenium is yellow-orange with well-developed gills. Its stipe, however, is lighter in color, either cream or pale yellow.

"From its appearance, it not only grows very big, but also has a bright yellow funnel-shaped cap, as if wearing a defending crown — quite regal, highlighting its unique status," Zeng said.

He and his students spent half an hour taking pictures and collecting specimens.

Subsequently, Zeng's research team discovered the same group of fungi in the same place on Aug 31, 2019, July 27, 2021, and May 17, last year.

Based on the specimens collected the second time, the research team announced the discovery of this new species.

The team collected specimens every time it located the mushrooms, brought them back to its laboratory and carried out in-depth research by combining morphological anatomy and molecular phylogeny.

Zeng said through comprehensive studies and comparative analysis of related literature, the cantharellus macrocarpus falls within the genus of the cantharellus, but its morphological characteristics and system position are different from those of the known species of the genus in the world. It was Zeng who named the new species. He added the word macrocarpus, which means "large-fruited", in reference to its size.

He said that nearly 200 types of chanterelles discovered in the world are edible, and the cantharellus macrocarpus is one of them. But cultivating them would be quite difficult because they have a symbiotic relationship with certain flowering plants in the forest, he explained.

Still, Zeng can't deny the nutritional value of the mushroom and recognizes its potential. He said that the new chanterelle species contains canthaxanthin, vitamin A, vitamin C and minerals, and the mushrooms are good for the eyes and stomach.

So far, eight types of mushrooms have been discovered in Hainan. Five were found by Zeng's research team.

Zeng said that the discovery of the new species not only shows that the Hainan Tropical Rainforest National Park is rich in biodiversity, but also shows the effectiveness of the park in ecological protection.

"Funded by the National Natural Science Foundation of China, our team will continue to research the mushrooms, which coexist with the tropical rainforest plants and play an important role in maintaining the ecological balance of the rainforest," he added.