ABOVE & BELOW: Young fig fruits of Ficus tarennifolia photographed in the Crocker Range at c. 1,000m by Quentin Phillipps.
UNDUK Ficus tarennifolia Corner (1960) SECTION: SYCOCARPUS
Latin: The leaves resemble those of Tarenna in the Rubiacea plant family. Unduk is the local Dusun name for this fig.
Plant: A small tree with cauliferous figs that mostly grow from the base of the trunk, locally common in wet forest on Kinabalu and the Crocker Range.
Fig: Very variable in shape and colour from green to dark crimson red. Figs finally ripen an orange brown. The area around the ostiole in young figs a is covered with layers of bracts but these appear to drop off as the fig matures.
Similar Species: The ripe figs by themselves may be confused with F. leptogramma and Ficus virecens with similar figs in large groups hanging from the trunk however the leaves are very different.
Distinguish: By the very distinctive young leaves with red veins and margins.
Distribution: Endemic to northern Borneo. There are no records south of the Sabah border. A locally common small tree on Kinabalu and the Crocker Range with a very wide altitude range 500-3,000m. According to Beaman (2004) it is the seventh most common fig recorded from Kinabalu. In my experience F. tarennifolia is the most common tree fig above 1,300m. Below 1,300m Ficus septica is more common but this may be because Ficus septica prefers secondary growth whilst F. tarennifolia prefers the forest understorey.
Notes: An individual in the Kinabalu Mountain Garden at Park HQ fruits regularly and has been photographed many times. This tree is believed to be a female tree – so the figs should attract dispersers. The fruit of this tree rot at the base but this is probably due to a lack of dispersers as the mountain garden is fenced.
Records from Gunung Palung (Laman & Weiblen) in SW Kalimantan are probably mistaken as their description does not fit F. tarennifolia.
