Wildlife Gardening/Taxon/Danaus plexippus

Danaus plexippus or the monarch butterfly is a large orange and black butterfly. Its primary habitat ranges from southern to northern, but it also sometimes visits southern Pacific countries as well as  and northern. Monarchs lay eggs only on milkweeds (genus ) and closely related plants. As the caterpillar feeds it accumulates toxins that make it repulsive to predators. Adults drink nectar from a wide variety of flowers, which they pollinate as they feed. With the onset of fall, monarchs undertake a long migration to and, from which they will return in the spring. Monarch populations have steeply declined in recent years, making them a popular target species for conservation gardeners. It is the state butterfly of and  as well as the state insect of, , , , and.

Although they contains poisonous substances, monarchs pose little risk to people, pets, or desirable wildlife. Nevertheless, the presence of unwanted monarchs may be discouraged in a garden by encouraging predators like, , , (Harmonia axyridis), and , among others.

Nomenclature
The monarch was originally described by Linnaeus as Papilio plexippus in 1758. Later that century Jan Krzysztof Kluk transferred it to the new genus Danaus, where it now resides. Nevertheless, during the intervening centuries several other scientific names now of purely historical interest were used, including D. archippus, D. menippe, and Anosia plexippus.

The name "monarch" is believed to be given in honor of King William III of England, whose secondary title Prince of Orange makes a reference to the butterfly's main color. Other common names depending on region include milkweed, common tiger, wanderer, and black veined brown.

Description
Monarchs' wingspans range from 8.9 to(-). The uppersides of their wings are tawny orange, with black veins. The wing margins are also black, and contain two series of small white spots. Monarch forewings likewise posses a few orange spots near their tips. Wing undersides are similar to their upper surfaces, but the tips of the forewings and hindwings are yellow brown and the white spots are larger. Monarch flight has been described as "slow and sailing". Although they have six legs like all insects, monarchs are members of the Nymphalidae (brush-footed butterflies), and their first pair of legs are non-functional evolutionary relics held tight against their body.

Variation
Adults are sexually dimorphic.

The shape and color of the wings change at the beginning of the migration and appear redder and more elongated than later migrants. Wings size and shape differ between migratory and non-migratory monarchs. Monarchs from eastern North America have larger and more angular forewings than those in the western population.

Identification
The monarch is closely related to several similar-looking butterfly species whose ranges abut or overlap with its own. It also has a, the viceroy, whose similar toxicity and coloration discourages predators from hunting either species.

Encourage
Monarchs obtain moisture and minerals from damp soil and wet gravel, a behavior known as mud-puddling.

Utilize
For taxa whose presence in the garden is enouraged without being harmed by article taxon use tables like above but from the pov of the attracted taxon