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Scientific name: Danaus plexippus

In the western hemisphere, there are two subspecies of the monarch butterfly: (1) Danaus plexippus plexippus of southern Canada, the USA,
Mexico, most Caribbean Islands, Central America, and northern South America; and (2) Danaus plexippus erippus of Peru, Bolivia, Chile,
Argentina, Uruguay, Paraguay and eastern Brazil. Neither subspecies has been recorded in northwestern Brazil.

Unlike most temperate insects, monarch butterflies cannot survive extended periods of freezing temperatures, so North American monarchs
fly south to spend the winter at roosting sites. In the spring, these overwintering monarchs fly north toward their breeding range. The
monarch is the only butterfly to make such a long, two-way migration, flying up to 4830 kilometers in the fall to reach its winter
destination. Monarchs east of the Rocky Mountains generally fly to overwintering sites in the
mountains of central Mexico, while monarchs west of the Rocky Mountains typically
overwinter along the California coast.

http://www.ecology.info/monarch-butterfly.htm

The Central American Monarch shown in the photo does not migrate to North America. The Central American Monarch population is
relatively sedentary, although short distance (10 to 100 km) seasonal migrations in Costa Rica between highland and
lowland regions in an east to west direction have been documented.

http://www.monarchwatch.org/read/articles/canmon1.htm