These  two Hose’s Langurs Presbytis hosei  (mother and infant) were feeding on immature Aristolochia vine leaves on Bukit Patoi Brunei in October 2018.  Aristolochia leaves are normally considered toxic or poisonous to humans but perhaps the young leaves  have yet to develop their poisons. Photos by Arlene Walshe.01 Hoses Langur Bukit Patoi 0C7A9496

02 Walshe Hoses Langur bukit Patoi 0C7A9501.JPG

Female Rajah Brooke’s Birdwing Trogonoptera brookiana butterfly resting on a dipterocarp leaf at the Belalong Canopy Walkway. These large butterflies lay their eggs on Aristolochia leaves, the caterpillars feed on the leaves, and  as a result  the adult butterflies are poisonous to birds. Male Rajah Brookes are fairly common in the forests of Temburong and may be seen puddling on damp earth especially where an animal has previously urinated. However females are rarely seen as they fly at canopy level.
Aristolochia rumphii.gif
This illustration is of Aristolochia rumphii which is only recorded from the Lesser Sunda Islands east of Borneo but is obviously closely related to the  Aristolochia species shown in the photographs  with leaves being eaten by the langurs.Enter a caption

Temburong, Brunei MAP