There are about 125,000 different species of moths, with many more yet to be discovered or properly identified. With so many different species of moth, there are also many different types of moth larvae, which we know better as caterpillars. Different families of moths have different defining characteristics of their larvae, making it a little bit easier to try and identify the vast number of caterpillars in the world.
Inchworms are a type of moth larvae that comes from the family Geometridae, which includes over 1,200 species of moths in North America alone. Inchworms get their name from the way they move and their size. Since they do not have any appendages in the middle of their body, they inch along in a looping motion. They are also commonly called loopers, spanworms and measuring worms. They have smooth and hairless bodies, and are normally about an inch in length. Green, brown and black are the most common colours for inchworms.
Some species of moth have larvae that are commonly called slug caterpillars, which actually belong to the family Limacodidae. They are called slug caterpillars because of the way the look and move, which resembles a slug. There are about 50 species of slug caterpillars in North America. Bodies of slug caterpillars can vary from having no hair to being very hairy, with some species having hair that can sting when touched. Green and brown are common colours, but they can also be very brightly coloured. A common example of this type of moth larva is the skiff moth, which is very small and sluglike in appearance.
Tent Caterpillars and Lappet Moths
Tent caterpillars and lappet moths belong to the family Lasiocampidae, and there are over 2000 species of this family of moths in the world. Caterpillars found in this family are hairy and normally large. Some species will live together in large nests spun of silk in trees, creating what look like large tents -- hence the name tent caterpillars. They can be very destructive to trees. Lappet moths get their name from the decorative skin flaps on their forelegs.
Giant Silkworm and Royal Moths
Giant silkworms and royal moths belong to the Saturniid moth family, which has about 1,500 species. The best way to describe giant silkworms and royal moths during their larval or caterpillar stage is that they are ugly. Many of these caterpillars will have large barbs and spines running down their body. These caterpillars are large, and the largest species of moth in North America is included with their group. They feed on a variety of trees and plants.