Danainae is a subfamily of the family Nymphalidae, the brush-footed butterflies. The group may be referred to as the Danaids (reflecting their previous rank as a family) or milkweed butterflies, as they often lay their eggs on various milkweeds on which their larvae (caterpillars) feed, though it also encompasses the clearwing butterflies (Ithomiini), and the Tellervini.
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 halia), and the soldier butterfly (or "tropic queen", Danaus eresimus). Of these, the monarch is by far the most famous, being one of the most recognizable butterflies in the Americas.