ABOVE: Ficus nervosa leaf and stipule. Photo by Shuai LIAO taken at Ranau, Sabah.
NERVED FIG Ficus nervosa B.Heyne ex Roth (1817) SECTION: OREOSYCEA
Latin: From the prominent side veins (nerves) on the underside of the leaf blade.
Habit: A large tree to 40 m with a straight white trunk and large buttresses at the base. As with the other figs in Section Oreosycea, there are no aerial roots or strangling roots.
Leaves: The leaves are very variable in size, dark green with a glossy upper surface. Only the lower half of the mid rib above is clearly pale. The side veins above are the same color as the leaf but slightly raised. The veins on the under surface are prominent. The basal veins are indistinct. Herbarium collections dry dark brown in clear contrast to F. vasculosa leaves which dry greenish with a waxy sheen
Fig: The figs have peduncles (stalks) up to 1 cm and hang from the ends of the branches. There is usually a stipe an oblong extension of fruit body to which the stalk is attached. The stalk (peduncle) has a circle of raised bracts. As with Ficus vasculosa the figs ripen yellow to bright red.
Sex: Monoecious (Bisexual). Both sexes combined in one plant.
Distinguish: Only 5 species of Section Oreosycea figs occur in Borneo. All have tall straight white trunks with prominent buttresses at the base and no strangling or hanging roots. Three species have figs which ripen red, F. albipila, F. vasculosa and F. nervosa. These 3 species can be distinguished by differences in the leaves and stipules
- The basal veins are very obvious in F. albipila but obscure or absent with both F. nervosa and F. vasculosa. The upper surface of the leaves of F. nervosa and F. vasculosa are similar with obscure basal veins but the the veins on the under surface of the leaf of F. nervosa are very prominent but only slightly prominent with F. vasculosa.
- The stipule of F. nervosa is unusually long (2-4 cm) and pointed and slightly hairy. The stipule of F. vasculosa is less than half the length 0.4 – 1.2 cm and smooth not hairy. The stipule of F. albipila is short, conical and hairy.
Borneo: Rare in Borneo but perhaps overlooked.
Sabah: Four herbarium collections from both the western and southern slopes of Kinabalu. Three recent sight records from roadsides near Kinabalu are hosted on this website and indicate that Ficus nervosa is probably locally common in the secondary forest of the Kinabalu foothills.
Brunei: No records
Sarawak: One record from Fairy Cave, at Bau near Kuching
Kalimantan: Three old records from hill forest near Bandjarmasin in SE Borneo.
Range: Although rare in Borneo F .n. pubinervis is a relatively common tree in the seasonally dry forests of the Indonesian islands including Java, Sumatra and Sulawesi. Common throughout the Philippines including Palawan. F .n. pubinervis was one of the first figs to colonize the bare volcanic cone of Rakata one of the Krakatau islands after the eruption of 1883.
Taxonomy: Berg & Corner (2005) recognize 3 subspecies;
(1) F. n. nervosa which is found from India to Taiwan (the large island)). This sub-species is very closely related to F. magnoliifolia and possibly con-specific.
(2) F. n. minor confined to Sri Lanka and India.
(3) F. n. pubinervis the sub-species found from two small islands off the S.E. coast of Taiwan (Green Island and Orchid Island) south to the Philippines, Borneo and Sumatra east to the Aru Islands near New Guinea. Absent from Singapore where F. vasculosa is relatively common.