Millipede Assassins: Saviours of Your Gardens

Millipede assassin bug crawling in the leaf litter of the coffee forest at the Poomaale Estate

In the lush greens of the Western Ghats, an assassin lurked, smartly hiding, looking for its prey, eagerly waiting for a chance to go for the kill. Its black colour with an uncommon highlight of blue – a sign of caution – drew us to it. We approached with calculated steps, careful not to alert it. Finally getting a glimpse of the big, broad bug, we realised that the health of our growing coffee forest was in the segmented hands of this assassin bug – the millipede assassin.

Millipede Assassin – Specialist Predators

Millipede assassin bugs (Ectrichodia crux) fall under a subfamily of assassin bugs (Reduviidae) with over 600 varieties of species. Their name comes from their area of specialisation – preying on millipedes. They are called ‘specialist’ millipede killers because there is no known defence a millipede has towards these big assassin bugs. Therefore, they become one of the few species worldwide that exclusively kill and feed on millipedes for nutrition and survival.

They are broad, distinctive and big assassin bugs with aposematic colouration (colours that repel or caution predators) – often blue, red or yellow. They are black assassin bugs with metallic colour highlights on their broad bodies. The adults can measure up to 22 mm. Their legs are black, segmented and typically longer than other insects. They have wings but prefer crawling.

Residents of the Garden

Usually found in leaf litter, millipede assassins tend to hide behind rocks and among other debris during the daytime and go looking for millipedes at night. They are also attracted to light, so you can often find them frequenting places with artificial lights. As a common garden bug, they can be found in numerous green spaces where millipedes are in significant numbers  – farms, orchards, forests and mangroves.

If you find one in your garden, it’s time to be delighted! Most people are wary of bugs and try to ward them off from their personal spaces. But finding a millipede assassin in your garden means you have a natural pest control system. They can define the health of your garden.

Millipede assassin bug crawling in the lead litter of the coffee forest at the Poomaale Estate

Attack Millipedes and More!

A specialist can be good at other areas too. 

Millipede assassins do more than just feed on millipedes. They have a diverse diet – ants, caterpillars, spiders and more. They approach slowly, attack swiftly and devour unhurriedly. The toxins they release when they strike the prey with their ‘beak’ (proboscis) turn the insides of the prey into a fluid. They then suck the fluid and leave the empty shell. Chemicals released by these millipede assassin bugs to repel predators are strong too. Therefore they predate more than they become prey. Hence they are an exclusively predatory species.

Welcome Them to Your Gardens and Food Forests

The presence of millipede assassins in your gardens and food forests can save you a lot of time and effort that goes into manual pest control. They are attracted to well-lit spaces with elements like rocks and leaves that help them to hide strategically. They also often love to sit on colourful flowers while waiting for their prey. Once a millipede assassin enters your garden, it’s best to leave them on their own as they can bite if provoked. Though their bites are not lethal to humans, they can cause rashes, swelling or itchiness.

Understanding the role of other living beings can help us lead a naturally optimised life. Even the millipede, considered a pest in this case, has a role to fill in the larger ecosystem. Doing our part and letting others do their part is key to an evolving world.