Habitat: The Glanville fritillary inhabits all types of grassland throughout continental Europe and large areas of Asia. In Great Britain the butterfly lives only on the coastal slopes of the Isle of Wight, an island filled with flowers and grassland. Its mild climate attracts the Glanville fritillary. A slight change in the climate has kept the Glanville fritillary from migrating further north in Great Britain. The butterfly was once found as far north as Yorkshire, but it prefers the milder, warmer regions rather than the cold.

Life cycle: The Glanville fritillary spends most of its one year life cycle as a caterpillar. After mating, the female lays her first batch of eggs in loose clusters under the tips of narrow leaved plantain or sea plantain leaves. She then feeds on buttercups, yellow vetches, or trefoils by sucking the nectar with her proboscis (tongue). The nectar helps her mature a second batch of eggs. After she lays them, the female dies. Caterpillars soon emerge from the eggs and feed on the plantain under a protective silken web. The caterpillars soon outgrow their tough skins. The skin splits, leaving a new, pliable skin that will be molted when it can be stretched no further.
By winter, the caterpillars have molted four times. 

They stop feeding and lie dormant until spring when they resume eating, becoming full grown after their sixth molt in early April. When the caterpillar sheds its skin for the seventh time, it emerges as a legless, non-feeding pupa (inactive form). It hangs from a plantain stem while the insect inside grows into an adult butterfly. After 15 days, the Glanville fritillary crawls out of the pupa, unfurling its wings so they will harden in the sun. After flexing its wings a few times, the butterfly flies off to feed, mate, and lay another generation of eggs.

Enemies: Glanville fritillaries can live for two to three weeks, but many survive for only a few days. Some dry up in the summer heat. Others are killed by butterfly eating spiders, such as the crab spider and the orb web spinner. The crab spider waits for butterflies in flowers, blending with the color of the petals. When the butterfly settles to drink the  nectar, the spider pounces and kills it. The orb web spider suspends its web between tall flower heads, snaring the butterflies as they pass.

Key Facts:
Characteristics:
Wings: 2 pairs
Wingspan: Female, about 2 in. Male, slightly smaller
Mouthparts: Caterpillar has biting jaws, adult has a coiled tubular proboscis

Life cycle:
Eggs: Laid in batches of up to 200 usually in May or June 
Hatching time: 3 weeks
Caterpillar to pupa: 10 months
Pupa to butterfly: 15 days

Lifestyle:
Diet: Caterpillar eats foliage of narrow leaved and sea plantains. Adults drink nectar
Lifespan: About 12 months from egg to death of adult

Related Species: There are many fritillaries in the family Nymphalidae, as well as more familiar species such as the peacock and red admiral.
Distribution: Throughout Europe (except much of Great Britain, Scandinavia, and southern Spain) and temperate Asia. A subspecies inhabits North Africa.
Conservation: The Glanville fritillary’s range in Great Britain is shrinking. Its future there depends on the conservation of its grassland habitat. The species flourishes elsewhere.

Life cycle of the Glanville Fritillary:
Eggs: Laid in clusters of about 200 on the leaves of narrow leaved plantain or sea plantain.
Caterpillar: The longest stage in the butterfly's life cycle. Hatches on food plant and eats until winter. Lies dormant until spring, when it resumes eating. It pupates after 10 months.
Pupa: Hangs from plantain. Tough outer casing protects the insect as it evolves into a butterfly.
Adult butterfly: Lives only a few weeks. Female dies shortly after laying her eggs.

Did You Know:
The Glanville fritillary is named for Lady Eleanor Glanville, 18th century butterfly enthusiast.
All insects have six legs, but the Glanville fritillaries and its relatives only use four. The front pair are too small for walking.
When alarmed, a feeding group of Glanville fritillaries will jerk their heads in unison. They may do it to confuse predators or keep tiny parasitic wasps from injecting their eggs into the caterpillars.

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