Butterfly vs. Moth

Butterfly vs Moth

Butterflies and moths belong to the order Lepidoptera. They both have 4 membranous wings (rarely wingless) with the hind wings a little smaller than the front wings.  The wings are largely or entirely covered with scales. They both have sucking mouth parts called a proboscis, usually in the form of a coiled tube.  The antennae are long, slender, and sometimes plumose (feathery appearance).  All butterflies have simple antennae that end in a swelling or "club". 

The principal characteristics of separating families of Lepidoptera are those of the wing venation, presence/absence of frenulum, presence/absence of ocelli, and characteristics of legs, mouth parts, and antenna.

Note: Most of these characteristics are difficult to see and knowledge of wing venation and other characteristics is required to make an accurate identification.  Most beginners may be able to identify a butterfly species with a good illustration, but moth species are much more difficult to identify (which make up the bulk of the order).

  • Butterflies

    Silvery Blue Butterfly

    Antennae: Have simple thread-like antenna with a clubbed tip.

    Color: Mostly brightly colored, but a few are dark brown with few markings.

    Body Shape: Generally slender and not especially pubescent (hairy).

    Wings: Wings are not linked--no frenulum.

    Resting Posture: Hold wings together above body when resting, but there are some exceptions.

    Forelegs: Forelegs are reduced, missing terminal segments

    Activity: Mostly diurnal (active during daylight)

  • Moths

    Polyphemus Moth

    Antennae: Have simple thread-like or "feathery" antenna without a clubbed tip.

    Color: Mostly a duller color with cryptic wing patterns, except some day-flying moths are brilliantly colored or have colorful "eyespots".

    Body Shape: Bulky and are often quite pubescent (hairy).

    Wings: Most moths have a frenulum which is a bristle present at the root of the hindwing which engages with a small hook on the forewing to join the wings together.  However, many moths do not have a frenulum.

    Resting Posture: Hold wings flat when resting.

    Forelegs: Fully developed

    Activity: Adult moths are generally nocturnal or crepuscular (active at dawn or dusk), but many are day-flying.