Significant Differences between Ficus leptocalama (L) and Ficus rubrocuspidata (R) according to Berg (2005)
Leptocalama: Confined to the hills and mountains of Sabah to 1300 m. Mostly on rocky stream banks.
Rubrocuspidata: Borneo endemic in forest up to 1,500 m sometimes creeping on rocks
SHAPE OF LEAF BASE
l: Always more or less decurrent/ unequal
2: Almost balanced/equal
Leptocalama: Obvious. Different from other veins, Running close to the margin to 1/6th of the lamina
Rubrocuspidata: Inconspicuous. Hardly different from the other side veins.
Leptocalama: Curved upwards always less than 90 degrees.
Rubrocuspidata: Departing at wide angles up to 90 degrees i.e.flattish
Leptocalama: Sub-scalariform (ladderlike)
Rubrocuspidata: Sub-reticulate (net like)
Leptocalama: On long leafless rooting branches
Rubrocuspidata: Scattered along twigs among the leaves
At most Ficus leptocalama can only be considered a variety of F. rubrocuspidata and the differences are not clear enough to separate them as two species.