Scientists identify 'alien' flowering plant

Ya Jidong takes photos of Thismia malipoensis in the nature reserve in 2019. CHINA DAILY

On Aug 13, 2019, Ya Jidong, a botanist from the Kunming Institute of Botany at the Chinese Academy of Sciences, and his colleagues walked into a patch of wet evergreen, broad-leaved forest in a karst valley in the Laoshan Provincial Nature Reserve in Malipo county, Yunnan province.

Working with the Germplasm Bank of Wild Species at the KIB, they were collecting germplasm materials from wild species, particularly seeds. By chance, they discovered a strange plant.

With a height of barely 4 centimeters above the ground, the tiny plant bore a striking resemblance to an "alien" due to its unique appearance.

"It looked more like a mushroom than a flowering plant, and it was something we had never seen before," Ya told China Daily.

They observed, measured and photographed the plant. As they walked a bit further, they found 10 more.

After returning to Kunming, capital of Yunnan, with the plant and conducting further studies, they found that the species is a member of the Thismia genus, which doesn't have green leaves and has eschewed photosynthesis in favor of a more unusual nutrient gathering process.

Thismia plants, commonly known as fairy lanterns, live entirely underground except for periods during the wet season, when their flowers rise above the soil.

"In the undergrowth of humid and dark forest, they only blossom for two or three weeks and then disappear," Ya said. "Even though we spent more than 100 days exploring the wild every year, we had never seen any Thismia species."

Three Thismia malipoensis flowers found in the Laoshan Provincial Nature Reserve in Malipo county, Yunnan province, in 2019. CHINA DAILY

After further study through collaboration with other researchers from the Xishuangbanna Tropical Botanical Garden under the CAS, they realized that the plant was a new species of Thismia.

On Feb 28, the researchers from KIB and XTBG described the new species, named Thismia malipoensis, in an article published in the international botanical journal Willdenowia. The discovery marked the eighth recorded species of Thismia in China.

Ya is the first author of the research article titled "Phylogenetic and biogeographical analyses of Thismia (Thismiaceae) support T. malipoensis as the eighth species in China".

According to the researcher, the unusual, elusive plants are herbs that completely rely on specific fungi for their supply of organic nutrients and only emerge above ground during flowering and fruiting periods. The colorful plants have a completely degraded photosynthetic function, possessing only a few scale-like leaves. The shape of their flowers is also unusual.

Thismia plants are almost exclusively distributed in tropical and subtropical areas of Asia and the Americas, with the exception of the T. americana from the central United States, which is thought to be extinct, according to the article.

Since the genus was established in 1845, Thismia species discovery had progressed very slowly, with only 40 species found worldwide through 1999. After 2011, at least one new species per year has been found. To date, 106 species and one variety have been recognized.

Thismia taiwanensis was the first species to be discovered in China, and the only one found until 2002.

However, when most fairy lanterns are found, there are only a small number of them in any area, said Dr Yu Wenbin from XTBG, one of the article's corresponding authors. Because they are highly reliant on a specialized fungal host, their distribution ranges may be restricted by the availability of the fungi.

"Thismia plants are usually very small, inconspicuous and out of the ground in the flowering and fruiting seasons usually for a very short period of time," Yu said. "Most Thismia species have extremely small population sizes and may be more sensitive to environmental changes. Their conservation presents unique challenges."

Given the high dependence of Thismia plants on specific mycorrhizal fungi for seed germination and seedling establishment, the most effective conservation strategy for these species involves in situ protection, emphasizing the preservation of their natural habitats, Yu said.