NEPENTHES BRACTEOSA & NEPENTHES HIRTELLA 2022

Both Endemic To Thailand

These two new species of pitcher plant (Nepenthes spp.), discovered in the hills of southern Thailand, have immediately been classifed as Critically Endangered. Each is found at only a single hilltop site – N. bracteosa on the summit of Khao Wang Hip in Nakhon Si Thammarat province and N. hirtella on Khao Shawaplab, Krabi province. This means that any signifcant disturbance or deterioration in their habitat could put them at risk of extinction.

This is a concern, because both sites are easily accessible. In fact, N. bracteosa was frst discovered from a photo taken by a tourist, while N. hirtella was discovered by a pitcher plant collector.

Pitcher plants – which all belong to a single genus – are carnivorous plants, with tendrils that form into a tube or globe-shaped trap to capture insects. Around 180 species have been recognized, and the number is increasing all the time. But while there’s been a lot of research into their diversity, their evolution is poorly understood, and their genome has not been fully sequenced.

As well as noting distinguishing characteristics in the shape of the leaves and pitcher shape, hairs and bracts, the researchers who described the new species used a technique called AFLP to examine genetic diferences. AFLP (amplifed fragment length polymorphism) uses selected fragments of DNA to create a genetic “fngerprint”. Researchers compared the new species with fve other Nepenthes from Thailand; this helped to clarify the diferences and relationships between them, and suggested that all pitcher plants in Thailand share a common ancestor.

Nuanlaong, S., Mekanawakul, M. and Suraninpong, P. (2022). Descriptions of two new species of Nepenthes (Nepenthaceae) from Thailand and their phylogenetic analysis based on AFLP technique species confrmation. Kew Bulletin 77(1): 105-120. doi.org/10.1007/s12225021-09997-6