New plant species discovered in Knuckles Range

Lankan researchers have described a new-to-science species of flowering plant, categorizing it as critically endangered because of its small and declining population and restricted range.

A report published by the Mongabay said that Impatiens jacobdevlasii is named in honor of Dutch botanist Jacob de Vlas, co-author of a series of illustrated guides on the more than 3,000 known flowering plants of Sri Lanka.

The Knuckles mountain range in central Sri Lanka is a UNESCO-declared World Heritage Site that’s home to a rich diversity of wildflowers. Among them are plants in the genus Impatiens, a new member of which has just been described by Sri Lankan researchers in the journal Phytotaxa — and which is already considered critically endangered because of its fleeting rarity.

The road to the discovery began in 2016, when researchers Champika Bandara, a Ph.D. candidate at the University of Sri Jayewardenepura, and Sanath Bandara Herath of the Open University of Sri Lanka (OUSL), were exploring the plant life along the banks of a stream in the Dothalugala area of the Knuckles range. It was here where they first spotted a purple impatiens flower that neither had ever seen before.

Fast-forward three years later, and as Bandara and Herath were deepening their study into what they suspected was a species new to science, another researcher, Bhathiya Gopallawa, a Ph.D. candidate at the University of Peradeniya, also encountered the same flowering plant.

Gopallawa’s discovery, however, occurred on a different trail in the mountains, called Thangappuwa, about 20 kilometers (12 miles) from the earlier location.

Realizing that he was looking at an undescribed species, and aware that Bandara and Herath were also working on an unknown impatiens, Gopallawa reached out to the others to compare notes.

The study that emerged from their collaboration, published this April, describes a new species that the researchers named Impatiens jacobdevlasii, after Jacob de Vlas, a Dutch botanist best known for co-authoring the Illustrated field guide to the flowers of Sri Lanka with his wife, Johanna. Published in three volumes from 2008-2019, the guide lists more than 3,000 native and introduced flower plants found on the island.

“I learned a lot from de Vlas’s field guide and also received the opportunity to get personal guidance to be a field botanist,” Bandara told Mongabay. He added that the field guide was also invaluable to other young botanists across Sri Lanka.

The new species is categorized as critically endangered in light of its low population, declining population trend, and limited distribution. Bandara said the Dothalugala population of I. jacobdevlasii has declined by 80% since that initial 2016 sighting.

The Dothalugala population is located near a stream along the Deanston–Dothalugala nature trail, and Thangappuwa population is found on wet, rocky surfaces along the Thangappuwa–Alugallena nature trail. Any road-clearing, weeding, construction or maintenance efforts by the authorities should prioritize the management and further conservation of this new species, Bandara said.