Plumbago Blue Butterfly
- Colour: the caterpillar (larva) is brown-pink or green with a black head.
- The male butterfly (adult) is brown with a blue-purple sheen, except on the outer margins of its wings.
- The female butterfly is brown with patches of white and an arc of dark spots along the margin of each hindwing (back wing). It also has a blue-purple sheen, but only on the inner part of its wings. Looking from underneath, both are mottled brown and white, with an arc of dark spots around the margin of each hindwing and two eye-spots near a “tail” on the back margin of each hindwing.
- The caterpillar has a flattened appearance and it tends to tuck its head under its body.
- Distinctive feature: the "marbled" effect on the underside of the butterfly's wings.
- Size: caterpillars are about 12 mm long; butterflies have a 2 – 3 cm wingspan.
- Diet: the caterpillar feeds on the flowers and buds of the native Plumbago species. The butterfly feeds on the nectar from these species and other native plants.
- Flight: when Plumbago species are flowering, and within a few metres of the ground.
- Breeding: the female lays single pale green eggs on the underside of a leaf or on the flower buds of Plumbago plants. Eggs are laid in the cooler months and have been reported to overwinter in cool areas, then hatch as caterpillars and later emerge from pupae as butterflies when the host plants (Plumbago species) are flowering. There are several generations each year.
What to Observe
- Presence (to establish the first and last sighting for the season)
- Egg laying
- Chrysalis (butterfly emerging from its shell)
ClimateWatch Science Advisor
We expect butterflies to appear earlier in the year as a result of climate change warming the Earth. They may also start appearing in new areas as warmer temperatures enable them to live in environments that were previously too cold for them.
When To Look
- From late summer to early winter (January to June) for butterflies in the Sydney region
- From late spring through summer for caterpillars in the Sydney region.
- Throughout the year for both caterpillars and butterflies in North Queensland
Where To Look
- In and near coastal areas of eastern Australia, from northern Queensland to southern New South Wales. It also occurs in the damp areas of the MacDonnell Ranges and Alice Springs regions in the Northern Territory.
- Most commonly in urban gardens around Plumbago plants, but also in open woodland around other native plants.
- Now extending its range southwards as it adapts to an introduced species of Plumbago which grows in temperate areas.
Braby, MF 2000. Butterflies of Australia: Their Identification, Biology and Distribution. CSIRO Publishing.
Braby, MF 2004. The Complete Field Guide to Butterflies of Australia. CSIRO Publishing.
Common, IFB and Waterhouse, DF 1981. Butterflies of Australia (revised edition). Angus & Robertson, Sydney.
Common Grass Blue Butterfly: the female doesn’t have any white patches, and neither the male nor female has the mottled brown and white colouring on the underside of its wings.
Did You Know?
Small ants are sometimes found near the caterpillars but they are not attended by ants as in many other butterfly species in the Family Lycaenidae.