Differences between Butterflies and Moths

Although the separation of Lepidopterans into "butterfly" and "moth" categories is a well-known distinction, the difference between a butterfly and a moth is not actually a standard taxonomic division. No rule is perfect, but generally the following conditions apply:

The most strict difference is in the feelers, or antennae. A butterfly has a thin straight pair of antennae which end in a small club, while moths usually have large feathered antennae for the males and thin, straight, unclubbed antennae for the females. This distinction is the basis for the non-standard taxonomy distinction between Lepidoptera "division" Rhopalocera ("clubbed antennae", the butterflies) and "division" Heterocera ("variegated antennae", the moths). There are a few exceptions to this rule. Not all moths have the feathering on their antennae, but they all lack the clubbed ends of a butterfly. On the other hand, one species of butterfly, Pseudopontia paradoxa from the forests of central Africa, bears thread-like antennae that lack the distinctive clubbed ends that normally identify butterflies.

Most moths have frenula, small barbs extending from the front of each hindwing. Butterflies do not have frenula. The frenulum is difficult to observe in living specimens.

The large majority of moths are nocturnal or crepuscular (active at dawn and dusk), although there are some diurnal (day-flying) species. There are few nocturnal butterflies.

Another major difference is in the pupa or metamorphosis stage when they change from caterpillar to adult insect. A moth normally spins a cocoon around its pupa to protect and conceal itself, while butterflies metamorphose inside a hardened shell called a chrysalis. Hawk moths, however, metamorphose inside a chrysalis, typically undergound.

Many, but not all, butterflies have bright colorful patterns on their wings. Nocturnal moths' wings are usually plain brown/grey/white/black, often with obscuring patterns of zigzags or swirls, to help camouflage them while they are resting in the daytime. However day-flying moths are often brightly-colored, particularly if they are toxic.

Moths rest with their wings spread out to their sides. Butterflies frequently fold their wings above their backs when they are perched and/or feeding, although they will occasionally "bask" with their wings spread for short periods. Some butterflies, like the skippers, may hold their wings either flat, or folded, or even in-between (the so-called "jet plane" position) when perched.

Moths tend to have very fat hairy or furry appearing bodies, while butterflies are slighter and smoother. Moths have larger scales that make them look more dense and fluffy. Butterflies on the other hand possess fine scales, that are actually more in density than in moths. However Moth scales seem to come off easily on touch, than butterflies, probably because of the large surface area of moth scales.

Moths' fore and hindwings are connected, while those of butterflies can move independently. The difference in wing articulation generally makes butterfly flight smoother, although there are considerable differences in flight patterns within the two groups also.

How do these butterflies get so much colour : - Butterfly Colouration