3 large moderately fruiting Dipterocarpus sp. have been spotted in Taman Botani Shah Alam: http://pericopsis.org/trees/id.php?tid=429669


3 fruiting individuals were spotted


Nuts with large reddish wings


Below the tree a few saplings with long reddish stipules enclosing new leaves


Thousands of nuts were on the soil, all of them were opened and eaten.

Nuts trapped within thin thorny palm leaves were also opened and eaten suggesting that the animal(s) responsible of the seed predation operate in the canopy (squirrels?) and not on the soil. Seed predation (insects and vertebrates) has been proposed as an explanation of the mast fruiting phenomenon as an antipredator adaptation. Indeed, if dipterocarpaceae are not fruiting during several years, predator populations are maintained at a low level. If suddenly most of the dipterocarpaceae are fruiting there will be not enough predators to eat all the seeds.


Finally I was able to find a few greenish and intact fruits. The black arrow indicates small and blunt tubercles on the calyx.

The calyx (the sepals of a flower) is fused in a tube that surrounds the nut. This distinguishes Dipterocarpus from the other genera of the Dipterocarpaceae family (Shorea, Vatica, Dryobalanops...). The identification of Dipterocarpus is confirmed by leaves with folded surfaces and wavy edges. The blade is thick, stiff and resistant to the decay.
I was unable to define the species. Blunt tubercles on the calyx would suggest D. rigidus, but according to C.F. Symmington's "Forester's Manual of Dipterocarps" (FRIM, revised in 2004) this species occurs only in the East of the Peninsula. The elongated reddish stipules on the young sapling would suggest D. baudii, but there are no hairs on the calyx tube.

This place should be checked again in a month for more mature nuts that could be germinated for ex-situ conservation.