Atala, Atala Hairstreak, Eumaeus atala Röber

The beautiful and rare Atala butterfly.
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Atala larva eating young coontie leaf.
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One rare butterfly!

The Atala butterfly's host plant is the coontie (Zamia pumila syn. Zamia floridana). In 1800’s Florida several factories here produced starch from the coontie plant. The coontie grows very slowly -- it can take 30 years to grow a plant that might have a large enough stem to weigh five pounds, so between the starch factories harvesting them and development in Florida destroying it's native habitat, wild coontie was almost wiped out.

Unfortunately for the Atala, the only native host plant of this butterfly is Zamia pumila. With very few places were the coontie was growing wild it was believed that the Atala butterfly had become extinct. From 1937 until 1965 the Atala was not found in the wild in Florida. Now that the coontie is popular for use in landscaping the Atala has made a comeback and is now common in southeast Florida. The Atala is found in Florida from Dade County north to St. Lucie and Indian River counties.

Identification

The adult Atala has a 38.1 mm wingspan with oval shaped wings that are black with metallic blue spots arranged in three bands on the underside of its hind wing with blue bands on the wing's top side. The underside of the Atala butterfly's hind wing near its abdomen as well as its abdomen are bright orange-red.

The head and thorax are black. Males have greenish patches on the front wing and top of the hind wing margins. Females have bluish patches across the top of the forewing.

Atala caterpillars, or larva, are orange-red with seven pairs of yellow spots running along the back. Atala larva are about 31.75 mm long.

The Atala's aposematic coloration throughout its life cycle is a warning to potential predators. Its host, Zamia pumila contains the highly toxic chemical cycasin which the Atala caterpillar stores in its tissues as it eats the tender young tips of the coontie. The cycasin is retained through all life stages of the Atala making them unpalatable and dangerous for predators to eat.

During her 10 day lifespan an adult female Atala may produce about 40 yellowish-white eggs which are deposited (singly or in clusters of 5 to 15 eggs) on newly emerging fronds or the top end of mature leaflets of the coontie plant. Eggs may also be deposited on female coontie cones.

Atala eggs hatch in 4 to 5 days. At the first stage (instar), the larva measures 2.5 mm. Younger instars are found in groups, but often become solitary when they reach full size. At the end of the 18 day larval period, the caterpillar will stop feeding, become stationary and attach itself to a coontie frond and molt into the pupa (chrysalis).

The pupal stage lasts about 10 days. At the end of this stage, the light orange-tan color of the chrysalis changes to dark brown. The outer shell becomes opaque and the adult butterfly emerges, usually in the early morning.