Hamadryas feronia (blue cracker, variable cracker)

Hamadryas feronia is an abundant widespread species found from Texas to Argentina, southern Brazil and Paraguay. 

This species is found in open forests at elevations from sea level up to 1,500m. Adults have been recorded on road surfaces, vegetation and rotting fruit.

Hamadryas feronia is difficult to spot due to its fantastic camouflage but can be found lying with it wings flat open on many trees.

Males make a loud clicking noise during flight. It is thought the noise is used to:

  • attract a mate
  • fight off rival males
  • scare away predators

No-one knows how the sound is produced, but it is probably made by clapping the wings together.


As with many neotropical species, this species has not been assessed globally on its conservation status using the International Union for the Conservation of Nature (IUCN) red list criteria.

Species detail

  • Hamadryas feronia male underside

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  • Hamadryas feronia

    Hamadryas feronia is an abundant widespread species found across the Americas. It is found in open forests and on roadsides and rocks. Find out more.

  • Hamadryas feronia
    Biology and behaviour

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About the authors

Ruth Carter
Work experience assistant
Department of Entomology

Blanca Huertas
Dr Blanca Huertas

Curator of the Museum's Lepidoptera collections.

A word from the authors

"We have chosen this species because of the intricate pattern on its wings - a great resource for camouflage. Hamadryas feronia has an interesting and unusual form of communication apparently, by making a clicking noise. Also this species proves that there is a lot more to be learnt about insect behaviour in the future which hopefully our young generation of researchers now doing volunteering and work experience will go on to study."

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