Actinote thalia pyrrha

An adult female Actinote anteas

rests on a mikania leaf

Biology and Life Cycle

The life cycle of A. thalia pyrrha is completed in 92-102 days in the insectary but decreases to 73-84 days with an increase in temperature.  Under these warmer conditions, the number of larval instars decreases from 6 to 5.

Eggs

Eggs are pale yellow and vase-shaped. Sizes vary from 0.62 - 0.7mm in length and 0.48 - 0.5mm in width, depending on their age. 

They increase in size after 5 days and become brick-red in colour before hatching.  Incubation of the eggs takes 10-15days.

Actinote eggs on the underside of a mikania leaf. 

Those that are reddish in colour are close to hatching.

This is a 6th instar larva of Actinote thalia pyrrha

Larvae

Larvae are grayish in colour with many spines on each body segment.  Each larva has 6 large black scoli (spiny projections) The duration of each larval stage is found in the table below as well as average sizes.  The larval period lasts an average of 63 days for males and 67 days for females.

Pupae

Larvae hang upside down from the mikania stems when they are ready to pupate.  They gradually harden and turn from bright green to a whitish colour.

Larvae progressively pupating

An adult female ovipositing her eggs on the leaf undersurface

Adults

Adults are large, colourful butterflies, brownish-orange with black markings.  The average wingspan is 56mm for males and 63mm for females. 

The males are paler in colour than females on the underside of the wings.  When light intensity and temperatures are low, the adults are inactive, sitting under the leaves, on stems or other surfaces.  The butterflies are most active at 29-30°C. 

Mating lasts several hours or overnight.  Oviposition starts 2-3 days after emergence and takes place in the mornings.  Eggs are laid under leaves in batches near the top of the plant.  The number of eggs per batch varies between 116-718.

Adults do not feed on the plant, surviving only on energy reserved in their body. They only mate and oviposit before they die within a week. Only the larvae(caterpillars) of Actinote butterflies feed on the leaves of the host plant.

References

De Chenon R., Sipayung A. and Sudharto P.  2002.  A new Biological Agent, Actinote anteas, introduced into Indonesia from South America for the control of Chromolaena odorata.  Proceedings of the Fifth Internaional Workshop on Biological Control and Management of Chromolaena odorata. Pp170-176.

VERY HUNGRY CATERPILLARS !

The rearing of an insect colony requires the preparation of hundreds of healthy mikania plants.

The project staff at Koronivia Research Station have the task of ensuring that the plants are completely free of pests and diseases before they are taken into the quarantine facility where the Actinote are reared.

On the left, Livai Vakatikati is shown pruning the mikania plants in the glasshouse.