Moth

Moths are a paraphyletic group of insects that includes all members of the order Lepidoptera that are not butterflies, with moths making up the vast majority of the order. There are thought to be approximately 160,000 species of moth,[1] many of which have yet to be described. Most species of moth are nocturnal, but there are also crepuscular and diurnal species.

While the butterflies form a monophyletic group, the moths, comprising the rest of the Lepidoptera, do not. Many attempts have been made to group the superfamilies of the Lepidoptera into natural groups, most of which fail because one of the two groups is not monophyletic: Microlepidoptera and Macrolepidoptera, Heterocera and Rhopalocera, Jugatae and Frenatae, Monotrysia and Ditrysia.[2]

Although the rules for distinguishing moths from butterflies are not well established, one very good guiding principle is that butterflies have thin antennae and (with the exception of the family Hedylidae) have small balls or clubs at the end of their antennae. Moth antennae are usually feathery with no ball on the end. The divisions are named by this principle: “club-antennae” (Rhopalocera) or “varied-antennae” (Heterocera). Lepidoptera differs between butterflies and other organisms due to evolving a special characteristic of having the tube-like proboscis in the Middle Triassic which allowed them to acquire nectar from flowering plants.[3]

The modern English word “moth” comes from Old English “moððe” (cf. Northumbrian “mohðe”) from Common Germanic (compare Old Norse “motti”, Dutch “mot”, and German “Motte” all meaning “moth”). Its origins are possibly related to the Old English “maða” meaning “maggot” or from the root of “midge” which until the 16th century was used mostly to indicate the larva, usually in reference to devouring clothes.

Moth larvae, or caterpillars, make cocoons from which they emerge as fully grown moths with wings. Some moth caterpillars dig holes in the ground, where they live until they are ready to turn into adult moths.[4]

Moths evolved long before butterflies; moth fossils have been found that may be 190 million years old. Both types of Lepidoptera are thought to have co-evolved with flowering plants, mainly because most modern species, both as adults and larvae, feed on flowering plants. One of the earliest known species that is thought to be an ancestor of moths is Archaeolepis mane. Its fossil fragments show scaled wings that are similar to caddisflies in their veining.[5]