Two-spotted Line Blue (Nacaduba biocellata)
Appearance: Very small. Undersite grey-brown with indistinct white lines and two subtornal black spots on the hind wing. Male upperside purple, female upperside brown with blue suffusion of varying extent.
Wingspan: 1.7 cm
Season: Several generations all year round.
Range: Widespread across Australia. Less frequent in TAS and in the far north of WA, NT, and QLD.
Habitat: Can be found in various habitats whereever the Acacia foodplants grow.
Photo: Male, Blue Mountains NP, NSW, 21 / 02 / 2010.
The Two-spotted Line Blue is one of Australia's most widespread butterflies. With a wingspan of only 1.7 cm it is also one of our smallest butterflies and therefore not always easy to spot. Occasionally the adult butterflies can be found in large numbers flying close to the ground near the Acacia foodplants. They also commonly feed on flowers where they are easy to find and watch.
There exist a few similar species in the genus Nacaduba and Prosotas, in particular along the east coast of Australia. The Two-spotted Line Blue can be distinguished from these through its indistinct white markings on the underside that are much less prominent than in the other species. In addition, the Two-spotted Line Blue has two prominent subtornal black spots on the hind wing underside each of which contains a few iridescent green scales.