(
Heliconius hecale) - note the clubbed antennae and slender body
Shape and structure of antennae The most obvious difference is in the feelers, or
antennae. Most butterflies have thin slender filamentous antennae which are club shaped at the end. Moths, on the other hand, often have comb-like or feathery antennae, or filamentous and unclubbed. This distinction is the basis for the earliest taxonomic divisions in the Lepidoptera: the
Rhopalocera ("clubbed horn", the butterflies) and the
Heterocera ("varied horn", the moths). There are, however, exceptions to this rule and a few moths (the families
Castniidae,
Uraniidae,
Apoprogonidae,
Sematuridae, and some members of
Sphingidae) have clubbed antennae. Some butterflies, like
Pseudopontia paradoxa from the forests of central
Africa, lack the club ends. The
hesperiids often have an angle to the tip of the antenna, with the clubs hooked backwards like a
crochet hook.
Wing-coupling mechanisms Many moths have a
frenulum which is a filament arising from the hindwing and coupling (matching up) with barbs on the forewing. The frenulum can be observed only when a specimen is in hand. There is only one known species of butterfly with a frenulum, which is the male regent skipper
Euschemon rafflesia. Some moths have a lobe on the forewing called a jugum that helps in coupling with the hindwing. Butterflies lack these structures.
Pupae Most moth
caterpillars spin a
cocoon made of silk within which they
metamorphose into the
pupal stage. Most butterfly caterpillars, on the other hand, form an exposed pupa made from a hardened protein, also termed a
chrysalis. File:Pupa3-cropped.jpg|Moths typically form a cocoon File:Monarch Butterfly Cocoon 3.jpg|Butterflies typically form a chrysalis There are many exceptions to this rule, however. For example, the
hawk moths form an exposed pupa which is underground.
Spongy moths sometimes form butterfly-style pupae, hanging on twigs or tree bark, although usually they create flimsy cocoons out of silk webbing and leaf bits, leaving the pupa exposed. The plume winged moths of the family
Pterophoridae also pupates without a cocoon and the pupa resembles the chrysalis of the
pierid butterfly. A few skipper butterfly larvae also make crude cocoons in which they pupate, exposing the pupa a bit. The
Parnassius butterfly larvae make a flimsy cocoon for pupation and they pupate near the ground surface between debris. moth (
Thaumetopoea pityocampa) - note the feathered antennae and fat furry body
Colouration of the wings Most butterflies have bright colours on their wings. Nocturnal moths on the other hand are usually plain brown, grey, white or black and often with obscuring patterns of zigzags or swirls which help
camouflage them from predators as they rest during the day. However, many day-flying moths are brightly coloured, particularly if they are
toxic. These
diurnal species evolved to locate their mates visually and not primarily by
pheromone as their drab nocturnal cousins. There are several exceptions to this rule, such as with the diurnal
Zygaenidae and Sytomidae families of moths, both of which have apposition eyes, or the
Hedyloidea family of butterflies, which are nocturnal and feature superposition eyes. In most cases where one species is found to be using the opposite type of eye than expected, it is because they are active during the opposite time of day than is normal for other butterflies or moths. ==Behavioural differences==