15 Most Alien Looking Caterpillars on Earth

Given that caterpillars are not themselves a species but just the in-between stage from butterfly or moth egg to pupa and then finally adult, they have made quite a name for themselves, especially as pests. Some of them are also so alien looking that one wonders where in the world they have come from.

Caterpillars belong to the Lepidoptera order, the insect order that is made up of butterflies and moths. Though the appearance and colouring of caterpillars can vary widely, common to most are their tubular, segmented bodies with three pairs of true legs and ten abdominal segments. They can have up to four pairs of prolegs (fleshy, stubby little structures coming out from the middle of the abdomen), making them quite the creepy crawlies.

Not all caterpillars look alien or even cute. As a rule of thumb – the more colourful and fuzzy a caterpillar is, the more likely it is to sting if touched. So, if in doubt, hands off!

The caterpillar of the Pale Tussock moth (Calliteara pudibunda), common in England and Wales, is usually greenish-yellow with ample tufts of hair.

Image: Waugsberg


Mugshot of a truly alien-looking critter

The saddleback caterpillar is one of the most common slug caterpillars and its sting is the severest, so watch out for this critter! Good that its distinct shape and markings make it hard to miss, though it is only about 1 inch long. Both ends of the caterpillar’s body are dark brown with brown “horns” that bear numerous spines. The middle of the body is green with a whitish margin and an oval spot in the middle, giving it the appearance of a saddle or blanket and therefore its name.