A small enounter with bugs

By Kakae Saiteu, Guide - Greystoke Mahale

On one of our nature walks from Greystoke Mahale, heading south from the camp, we encountered two brightly coloured bugs - the cotton stainer assassin bug and a cotton stainer bug. Both appeared in bright red, yellow and black colours. The cotton stainer assassin bug is a carnivore, which feeds on other insects---preferably on cotton stainer bugs. The cotton stainer bug feeds on plants, most species of which are in the ‘cotton family’ (the Malvaceae family).

Although the cotton stainer assassin bug and the cotton stainer bug feed on completely different foods, they have similar mouthpart structures called a ‘rostrum’. The rostrum is an organ which is long and well-adapted for piercing and sucking sap or blood from victims. When not in use, the rostrum is folded back beneath the head and between the legs.













On this particular day, we found these two bugs on two different leaves on the same branch. The assassin bug was on the higher leaf and the stainer bug was about 3 centimetres below. Neither of them was moving - which initially made us think that these were a male and a female of the same species. After further observation, however, we saw that the two bugs looked only superficially similar and that they were clearly not of the same species. The assassin bug was mimicking the stainer bug. This mimicry allows the assassin bug to get very closer to the stainer bug before attacking.

After about one minute of watching them, the stainer bug started to move along the leaf. Suddenly the assassin bug jumped and caught the stainer bug using its powerful forelimbs. The assassin bug then moved its rostrum from the head to the abdomen of the victim, before piercing it. The victim move slightly at the moment it was caught but suddenly became motionlessc - suggesting that it might have been paralyzed. Ignoring our presence, the assassin bug continued turning and overturning the victim while driving its rostrum into different parts of the stainer bug. After about 15 minutes we left---with the predator still piercing its prey.