Ancient 'ant from Mars' discovered in Amazon rainforest

A new species of predatory insect known as the 'ant from Mars' because of its unusual alien characteristics, has been discovered in the Amazon rainforest.

The ant, Martialis heureka, is blind and lives underground and was probably a descendant of the very first ants to evolve. It is two to three millimetres long, very pale, has no eyes and a large lower jaw.

It was discovered in Brazil by evolutionary biologist Christian Rabeling from the University of Texas, who said the ant had a combination of characteristics that had never been recorded before.

Rabeling said his discovery will help biologists better understand the biodiversity and evolution of the insects.

'This discovery hints at a wealth of species, possibly of great evolutionary importance, still hidden in the soils of the remaining rainforests,' he wrote in the Proceedings of the National Academy of Sciences.

Rabeling collected the only known specimen of the new ant species in 2003 from leaf-litter at the Empresa Brasileira de Pesquisa Agropecuária in Manaus, Brazil.

He and his colleagues found that the ant was a new species and subfamily of ants after analysing DNA from the ants' legs.

Ants evolved over 120 million years ago from wasp ancestors. They probably evolved quickly into many different lineages, with ants specializing to lives in the soil, leaf-litter or trees.

'This discovery lends support to the idea that blind subterranean predator ants arose at the dawn of ant evolution,' Rabeling said.

He speculated that the new ant species evolved adaptations over time to its subterranean habitat, such as its loss of eyes, while retaining some of its ancestor's physical characteristics.