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For other uses of the term "butterfly" see: butterfly (disambiguation).
A butterfly is a flying insect of the order Lepidoptera belonging to one of the superfamilies Hesperioidea (the skippers) and Papilionoidea (all other butterflies). Many butterflies have striking colours and
patterns on their wings. People who study or collect butterflies (or the closely- related moths) are called lepidopterists.
The four stages in the lifecycle of a butterfly
Unlike most insects, butterflies do not experience a nymph
period, but instead go through a pupal stage which lies between the larva and the adult stage (the imago).
Egg
Butterfly eggs consist of a hard-ridged outer layer of shell, called the chorion. This is lined with a thin coating of
wax which prevents the egg from drying out before the larva has had time to fully develop. Each egg contains a number of tiny
funnel-shaped openings at one end, called micropyles; the purpose of these holes is to allow sperm to enter and fertilize
the egg. Butterfly and moth eggs vary greatly in size between species, but they are all either spherical or ovate.
Larva
Larvae, or caterpillars, are multi-legged eating machines. They consume
plant leaves and spend practically all of their
time in search of food. As they mature their skin is shed several times.
Pupa
When the larva has eaten enough it will will either spin a cocoon or form a chrysalis. The larva usually moves to the underside of a leaf. To form a cocoon it spins
a silk-like thread around itself. A chrysalis is formed by hardening bodily secretions. A larva completely covered by a cocoon or
chrysalis is called a pupa. Inside its protective shell the larva will transform into a butterfly (or moth), a process known as
metamorphosis.
Butterfly
As Lepidoptera, butterflies have four wings, but unlike moths, the fore and hindwings are not hooked together, permitting a
more graceful flight. A butterfly has six legs; the larva also has six true legs and a number of prolegs. After it emerges from
its pupal stage it cannot fly for some time because its wings have not yet unfolded. A newly emerged butterfly needs to spend
some time 'inflating' its wings with blood and letting them dry, during which time it is extremely vulnerable to predators.
Many species of butterfly are sexually dimorphic. Some
butterflies, such as the Monarch butterfly, are migratory.
Butterflies are often confused with moths, but there are a few simple differences between them, including colour, habits, and
pupating appearance. See the difference between a butterfly and a moth.
Butterflies live primarily on nectar from flowers. Some also derive nourishment from
pollen, tree sap, rotting fruit, dung, and dissolved minerals in wet sand or dirt.
Butterflies are also pollinators.
Classification
Although the butterflies are classified in two superfamilies, Hesperioidea and Papilionoidea, these are sister taxa, so the butterflies collectively are thought to constitute a true
clade. Some modern taxonomists place them all in superfamily Papilionoidea,
distinguishing the skippers from the other butterflies at the series level only. There is only one family in the Hesperioidea (or
series Hesperiiformes), the skipper family Hesperiidae. The families in the
Papilionoidea (or Papilioniformes) are:
- Swallowtails or Birdwings, Papilionidae
- Whites or Yellow-Whites, Pieridae
- Blues and Coppers or
Gossamer-Winged Butterflies, Lycaenidae
- Metalmark
butterflies, Riodinidae
- Snout butterflies,
Libytheidae
- Brush-footed butterflies, Nymphalidae
Some older taxonomies recognize additional families, for example Danaidae, Heliconiidae and Satyridae, but modern
classifications treat these as subfamilies within the Nymphalidae.
There are between 15,000 and 20,000 species of butterflies worldwide. Some well
known species include:
- Small Tortoiseshell, Nymphalis urticae
- Small White, Artogeia rapae
- Green-veined White, Artogeia napi
- Monarch Butterfly, Danaus plexippus
- Red Admiral, Vanessa atalanta
- Painted Lady or Cosmopolite, Vanessa cardui
- Peacock, Inachis io
- Xerces Blue, Glaucopsyche xerces
- Gulf Fritillary, Agraulis vanillae
- Black swallowtail, Papilio polyxenes
- Spicebush swallowtail, Pterourus
troilus
- Morpho genus
Survival
Butterflies (and their immature stages) have many natural enemies such as:
Ants
Ants will sometimes attack a larva in hordes. However, there are actually some species of ants that keep myrmecophilous (ant
loving) butterfly larvae as cattle, taking a larva into their nest, feeding it leaves on one end and milking it for honeydew on the other. This symbiotic
relationship can turn to the larvae becoming myrmecophageous (ant-eating). The ants actually tolerate the larvae even while they
eat the ant pupae.
Birds
Some butterflies have evolved 'eye' like markings on their wings, scaring off some birds. Also, since some birds attack the eyes of an animal first, the butterfly has a chance of escaping in the
confusion when the bird simply pokes a hole in one of the wings.
Etymology
An erroneous etymology claims that the word butterfly came from a shift of
letters in "flutterby"; however, the Old English word was
buttorfleoge and a similar word occurs in Dutch, apparently
because butterflies were thought to steal milk.
Field guides to butterflies
- Butterflies of North America, Jim P. Brock and Kenn Kaufman (2003)
- Butterflies through Binoculars: The East, Jeffrey Glassberg (1999)
- Butterflies through Binoculars: The West, Jeffrey Glassberg (2001)
- A Field Guide to Eastern Butterflies, Paul Opler (1994)
- A Field Guide to Western Butterflies, Paul Opler (1999)
- Peterson First Guide to Butterflies and Moths, Paul Opler (1994)
- The Millennium Atlas of Butterflies in Britain and Ireland by Jim Asher (Editor), et al.
- Pocket Guide to the Butterflies of Great Britain and Ireland by Richard Lewington
- Butterflies of Britain and Europe (Collins Wildlife Trust Guides) by Michael Chinery
References
- Pyle, R. M. (1992) Handbook for Butterfly Watchers. Houghton Mifflin. Originally published, 1984. ISBN 0-395-61629-8
- Heppner, J. B., 1998. Classification of Lepidoptera. Holarctic Lepidoptera, Suppl. 1.
External links
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