Research assistant Jeisin Jumian poses next to the rare Rafflesia keithii in the Silabukan forest reserve.
KOTA KINABALU: Forestry researchers have found a rare species of the Rafflesia parasitic flowering plant called the Rafflesia keithii in the Silabukan forest reserve, some 50km east of Sabah’s eastern Lahad Datu district.
The 14-member team from the Sabah Forestry Department were conducting a forest inventory when they stumbled upon the plant in full bloom recently.
Endemic to Borneo, the Rafflesia keithii is the largest of three species of Rafflesias found in Sabah.
“This new discovery is considered rare and exciting because the species has never been recorded this far east of Sabah,” said Dr Joan Pereira, a senior botanist at the Forest Research Centre in Sandakan, in a statement.
The field team from the department was carrying out a forest inventory in the Silabukan Forest Reserve as part of a collaboration with WWF-Malaysia to establish a land cover monitoring system for the larger Tabin landscape, covering about 450,000ha.
According to the Sabah Forestry Department, the easternmost record of Rafflesia in Sabah was a lone record from the Danum Valley Conservation Area.
“Botanical records show Rafflesia keithii occurring primarily on the west coast of Sabah such as along the Crocker Range as well in Tambunan, Kota Marudu, and the Ranau districts including in Kinabalu Park, at altitudes ranging from 250m to 940m.
“The spectacular bloom in Silabukan measured 47cm in diameter and was growing on volcanic soil at an altitude of 630m.
“An unopened Rafflesia bud was also observed next to the open flower whilst another bud was found some 20m away,” the department added.
The host plant of this parasitic species was identified as Tetrastigma diepenhorstii. All Rafflesias depend on host plants from the genus Tetrastigma.
Meanwhile, Chief Conservator of Forests Datuk Frederick Kugan said apart from providing information on floristic composition and soils, the Forestry Department also expected to produce a high resolution carbon stock map for the Tabin landscape as an output of the inventory.
Kugan congratulated the field team for the interesting find, saying that it highlights the importance of the Silabukan forest reserve as a Class I Protection Forest.
