The very variable leaves of Ficus sinuata. Both Ficus macilenta and Ficus sinuata (illustrated above) have very similar growth habits. Both are medium sized straggling bushes and the leaves are both very similar and very variable. However , Berg and Corner (2005) placed them in two entirely different taxonomic sections, Section Sycidium (F. sinuata) and Section Eriosycea (F. macilenta) based on the internal structure of the fig fruits.
FICUS SINUATA Thumb (1786) SECTION: SYCIDIUM
Latin: Sinuous, bending referring to the wavy or undulating leaf margin.
Small climber to 6 m common in Sarawak and Kalimantan but rare in Sabah apart from Kinabalu where it is common between 900-1, 500m.
Medium size leaves 4-15cm but up to 26 cm long by 1.5-8cm wide with a glossy sometimes corrugated surface and wavy leaf edge. In some collections the leaf margin is dentate (bluntly toothed. The leaves are distichous and almost symmetric with a long pointed drip tip.
Sex: Dioecious.
Small figs (0.6-1.2 cm) are both cauliflorus and ramiflorus ,scattered in small clusters in the leaf axils and along the bare branches. Figs ripen orange to dark red.
Habit: A large bush with long ungainly branches, common around Kinabalu Park HQ growing on the ground and along the Tenompok road where it grows on trees and rocks at the forest edge. There is an established plant growing immediately behind the Liwagu restaurant at Kinabalu Park HQ on a tree stump and others on the slope above the Balsam Restaurant at Kinabalu Park HQ.
Similar species: F. rubrocuspidata.
Distinguish: (1) F. rubrocuspidata figs are tiny c. half the size of F. sinuata figs. (2) F. rubrocuspidata leaves are usually smaller than F. sinuata and are normally flat whilst the leaf margins of F. sinuata are wavy. (3) F. sinuata leaves are extremely variable in shape and size whereas F. rubrocuspidata leaves are less variable. (4) The veins of F. sinuata leaves are impressed above giving the leaf a corrugated appearance.
Distribution: Locally common on Kinabalu but rare elsewhere in Sabah. Common in Sarawak and throughout Kalimantan.
Range: NE India, Thailand, Malaya, Sumatra, Java and Borneo.