These small-sized butterflies are commonly called 'metalmarks'. There are more than 1300 species, mostly from the American tropics.
Metal marks were often included as a subfamily of the Lycaenidae but although these butterflies are their closest relatives, today they are classified as a separate family.
Most of the species can be found in Central and South America, where they have a spectacular array of colour patterns.
Some of their caterpillars have been found to be able to communicate with ants.