Borneo’s extraordinary bug life
A tropical forest fireworkAnother prominent group of insects includes the order Lepidoptera (butterflies), symbolized by the famous Rajah Brooke's birdwing (Trogonoptera brookiana), with its vivid wing motif of green triangles. The appearance of butterflies is seasonal: some species are abundant at certain times of the year but disappear completely in other months.
Borneo’s silent armiesAnts are some of the most abundant and diverse animal groups in tropical ecosystems, and they function at many levels:
- as predators and prey
- as detritivores (organisms that recycle decomposing organic matter)
- as mutualists (an interaction between two species where both derive benefit).
Borneo may have more than 1,000 species of ants, with representatives of about 30% of ant genera and about 7% of ant species globally.2
More than 3 species discovered every month during the past 15 years
Ants living with the ‘enemy’
Why doesn’t the pitcher plant eat the carpenter ant too? The accumulation of excess prey in pitchers can lead to putrefaction of the contents, disrupting the pitcher's digestive system. When carpenter ants are present, this risk is significantly reduced. It seems that sometimes, being close to a carnivorous organism is the best way to stay alive.3
One termite species is the processional termite Hospitalitermes, which is found across Southeast Asia. The species forages for lichens and other plants, primarily from tree trunks and the rainforest canopy.6
Another group of Borneo invertebrates that play a critical role in recycling dead matter is the millipedes (class Diplopoda). Species of this class of invertebrates, which is estimated to have existed on Earth for over 400 million years, have developed a close association with forests ecosystems by playing an important role in the decomposition of wood and leaf litter.7
- A new Heteroptera species, a bamboo-dwelling, semi-aquatic bug, which exploits a unique ecological niche in the water-filled cavities of various bamboo species. The bug enters the cavities through small holes bored by insects or woodpeckers and mainly feeds on other insects trapped on the water surface.
- Three new crab species from the genus Parathelphusa were described from 3 different sites in Borneo. This genus comprises 35 species, which are all found mainly in Sumatra, Borneo and Peninsular Malaysia.
World's longest insect
Despite its size, very little is known about its biology and ecology, although it was described in 20081. It is believed to inhabit the high rainforest canopy making it especially elusive and difficult to study.
Also known as ‘Chan’s megastick’ after the scientist that donated this particular specimen to the Natural History Museum in London, this species is the current title holder for a number of world records.
1 Stork, NE. 1991. The composition of the arthropod fauna of Bornean lowland rain forest trees. Journal of Tropical Ecology [J. TROP. ECOL.]. Vol. 7, no. 2, pp. 160-180.
2 Mohamed M. Identification Guide to the Ant subfamily of Borneo. Accessed April 9 2006.[PDF]
3 Clarke CM, Kitching RL. 1995. Swimming ants and pitcher plants: A unique ant-plant interaction from Borneo. Journal of Tropical Ecology [J. TROP. ECOL.]. Vol. 11, no. 4, pp. 589-602.
4 Wikipedia. Termites. Accessed April 9 2006.
5 British Natural History Museum. Termite diversity and its role in tropical ecosystems. Accessed April 9 2006.
6 Miura T., Matsumoto T. 1997. Diet and nest material of the processional termite Hospitalitermes, and cohabitation of Termes (Isoptera, Termitidae) on Borneo Island. Insectes Sociaux [INSECTES SOC.]. Vol. 44, no. 3, pp. 267-275. 1997.
7 The Field Museum. Introduction to Millipedes. Accessed 08 April 2006.