9 Blue Butterfly Species You Won't Believe Are Real

The Blue Morpho is one of the largest and most recognizable blue butterfly species in the world. With a wingspan of about 5 to 8 inches (13 to 18 cm), its dazzling upper surface is a brilliant blue, edged with a black border.

Males are more vibrant than females, a common trait among butterflies. Adults feed on rotting fruit and fly mostly during the day in tropical forests.

An endangered species found primarily in Oregon's Willamette Valley, the Fender's blue butterfly has a wingspan of about one inch (2.5 cm). The males display striking blue coloring on their upper surface, while females appear brown with white-rimmed spots.

This small butterfly depends heavily on lupine plants for laying eggs and for its caterpillars to feed on. Conservation efforts, including a recovery plan by the U.S. Fish and Wildlife Service and work from The Nature Conservancy, aim to protect this species' dwindling habitat.

This small butterfly shines with a silvery-blue sheen on the upper side of its wings. Found in various grasslands and open spaces, silvery blues often display black spots along the undersides their wings.

Like many other blue butterflies, the caterpillars feed on a specific range of plants. These butterflies produce one generation each year, with adults often seen by early June.

Widespread across Europe and parts of Asia, the Common Blue is known for its vivid coloration and adaptable nature. Males flaunt bright blue wings with a thin black border, while females can appear more brown with orange spots and white edges.

These butterflies thrive in meadows, grasslands and even disturbed habitats. Despite their name, their beauty is anything but ordinary.

A North American native, the Eastern tailed-blue has delicate tails extending from the edges of its hind wings.

The upper side of the males' wings is a rich blue, while females are often grayish with a hint of blue. The underside of their wings typically shows a series of black spots, helping with identification.

Adults are active in spring and summer — and like other butterflies, they rely on specific plants for their larvae.

The Karner Blue is another North American species, and one that is federally listed as endangered in the United States. Its habitat is closely tied to wild lupine plants, which the caterpillars feed on. Habitat fragmentation and invasive species have contributed to this butterfly’s decline.

With a wingspan of about one inch (2.5 cm), the males show brilliant blue coloring, while females are typically brown with blue highlights.

Found in southern Europe, the Adonis Blue is named for its intense, sky-blue wing color. Males are particularly vivid, while females tend to be brown.

This butterfly prefers chalk grasslands, and populations can fluctuate with seasonal changes and land use. It is sensitive to grazing pressure and requires specific plants for its larvae to thrive.

This species inhabits coastal areas and mountainous regions in the western United States. Boisduval’s Blue butterflies are recognizable by their pale blue wings and white fringe. Males are more colorful than females, which are usually brown.

Caterpillars feed on legumes, and adults are often seen flying near their host plants.

This butterfly, found in parts of Europe and Asia, is known for the unique greenish hue on the underside of its wings. The upper wings of the male are blue, while the female is generally brown. These butterflies are active during the spring and prefer open, sunny habitats with plenty of flowers.

We created this article in conjunction with AI technology, then made sure it was fact-checked and edited by a HowStuffWorks editor.