Psychonotis caelius

Psychonotis caelius, the small green banded blue, is a species of butterfly of the Lycaenidae family. It is found in New Guinea and adjacent islands and along the eastern coast of Australia.

The wingspan is about 30 mm. Adult males are blue with a large white patch on the hindwings. Females are black with a large white patch on the wings.

The larvae feed on Alphitonia excelsa and Alphitonia petriei. It lives on the underside of a leaf of the host plant. They are pale green and hairy. Pupation takes place in a cream coloured pupa with brown markings, which is attached to the underside of a leaf.