[2] They feed on colonial cnidarians such as Portuguese man o' wars, blue buttons, and purple sails.

They can produce painful and potentially dangerous stings when handled, as they store the venomous nematocysts of their prey.

[1] The genus Glaucus was established by monotypy in 1777 by the British naturalist Johann Reinhold Forster.

[4] He described specimens of Glaucus atlanticus recovered during the second voyage of James Cook aboard HMS Resolution.

[8] In 2014, a careful DNA and anatomical study of the genus unexpectedly revealed the presence of a species complex.