Rarest rafflesia species found growing in Sabah forest reserve

KOTA KINABALU, Sept 30 — Sabah’s endemic Rafflesia tengku-adlinii, was found in Bukit Monkobo and Bukit Mentapok Forest Reserve in the north-central part of the state.

The discovery was made during a recent Heart of Borneo (HoB) scientific expedition in mid-August, 2024 by a group of researchers, led by John Sugau, Dr Reuben Nilus and Razy Japir from the Forest Research Centre of the Sabah Forestry Department, with cooperation from Beluran District Forestry Office and TSH Resources Berhad.

This species is the rarest among the three rafflesias found in Sabah. Previously, it is only known in the western and central parts of Sabah, in the Trus Madi Range and Maliau Basin Conservation Area.

At least three populations of the species were encountered in Gunung Monkobo and another one in Gunung Mentapok.

Rafflesia tengku-adlinii was named after one of Sabah’s foremost conservationists, Datuk Dr Tengku D. Z. Adlin, and discovered in 1987 by the late Prof Kamarudin Mat Salleh in the Trus Madi Range.

The flower is small (20.5-23.2 cm in diameter) compared to the other two species and it has homogeneous orange colour perigone lobes with roundish orange warts. Rafflesias are parasitic plants that depend on a liana, Tetrastigma (Vitaceae) to survive. The host plant of this species was identified as Tetrastigma diepenhorstii.

The Chief Conservator of Forests, Datuk Frederick Kugan, emphasized that the discovery of this rare rafflesia species would enhance the protection and conservation of this reserve which has been regazetted as a Class I Forest Reserve (Protection) in 2015. This reserve of 5,443 ha is almost entirely enclosed by Ulu Tungud Forest Reserve except for the southern part which is bordering private land.

The Ulu Tungud FR is licenced to TSH Resources Berhad. Although gazetted as ‘Bukit’, both are more popularly known as ‘Gunung’ by the locals.

The Monkobo (1,829 m) and the adjacent Mentapok (1,581 m) peaks are among the lesser known and much unexplored mountains in north-central part of Sabah. — The Borneo Post