Milkweed butterfly

For the mythological fifty daughters of Danaus, see Danaides.

Milkweed butterflies
Three milkweed butterflies. Clockwise from left: Dark Blue Tiger (Tirumala septentrionis), Striped Blue Crow (Euploea mulciber), and Common Tiger (Danaus genutia).
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Lepidoptera
(unranked):	Rhopalocera
Family:	Nymphalidae
Subfamily:	Danainae
Tribes
Danaini Tellervini Ithomiini but see text.
Synonyms
Danaidae

Milkweed butterflies are a subfamily, Danainae, in the family Nymphalidae, or brush-footed butterflies. They lay their eggs on various milkweeds on which their larvae (caterpillars) feed. Historically, this group had been considered a separate family, Danaidae.

Some 300 species of Danainae exist worldwide. Most of the Danaini are found in tropical Asia and Africa, while the Ithomiini are diverse in the Neotropics. Tellervini are restricted to Australia and the Oriental region. Four species are found in North America: the Monarch butterfly (Danaus plexippus), the Queen (Danaus gilippus), the tropical milkweed butterfly (Lycorea cleobaea), and the soldier butterfly (or "tropic queen", Danaus eresimus). The best known milkweed butterfly is the Monarch butterfly.

Taxonomy

Milkweed butterflies are now classified as the subfamily Danainae within the family Nymphalidae. However, the previous family name Danaidae is still occasionally used. The fossil milkweed butterfly Archaeolycorea is known from the Oligocene or Miocene Tremembé Formation of Brazil. It provides evidence that the present milkweed butterflies originated more than 20-30 million years ago.

Characteristics

Danaus chrysippus, male with anal hairs

Larvae have thoracic tubercles and use plants within the family Apocynaceae that often contain latex-like compounds in the stem as hosts. Adults are aposematic.

Threats

Numerous wasps are parasitoids of milkweed butterfly caterpillars.

The extensive modification of landscapes in the United States and Canada, large-scale use of pesticides, and increased deforestation in Mexico threaten the migratory Monarch butterfly.

Further reading

• Ackery, P. R. & Vane-Wright, R. I. 1984. Milkweed butterflies, their cladistics and biology, being an account of the natural history of the Danainae, a subfamily of the Lepidoptera, Nymphalidae. ix+425 pp. London.

External links

• Danainae