There exists over 350,000 documented beetle species in the world today. To put this number in perspective, there only exists around 4,000 mammal species, and with the possible exception of wasps, beetles are the most species-rich insect species in existence. In fact, there are more beetle species on earth than plant species, as the amount of documented plant species is around 250,000. Considering how abundant beetle species are, it should not come as a surprise to learn that some species have evolved some odd defensive behaviors. One of these odd beetle species is commonly known as the bloody-nosed beetle. This species, which is officially known as Timarcha tenebricosa, gets its name from its ability to bleed on reflex. Strangely enough, this beetle species displays blood within its mouth in order to deter attacks from onlooking predators.
The bloody-nosed beetle can be found during most months within grassland regions. These metallic, flightless beetles prefer to feed on cleavers, which is a plant commonly found on hedgerows. Most bloody-nosed beetles emerge during the month of April in order to breed. This is the same time of year that sees over-wintering bloody-nosed beetle eggs hatch into larvae. The larvae are noticeable during the spring and summer season due to their large body size and metallic appearance.
When this beetle becomes disturbed or feels threatened, it opens its mouth in order to show a droplet of blood. In order to do this, the bloody-nosed beetle deliberately breaks membranes within its mouth to induce bleeding. When predators see the resulting drop of haemolymph (which is analogous to human blood) in the beetle’s mouth, they avoid attacking. This is because this species’ haemolymph is foul-tasting to predators, causing predators to cringe upon seeing the disgusting red and orange-colored fluid. This unique defense mechanism works to save this beetle species from becoming dinner in many circumstances.
Have you ever witnessed insect communication of any kind?