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Contents > Butterflies > Migrant > Blue Moon

Blue Moon


Hypolimnas bolina nerina

Distribution & Status Blue Moon Distrubtion Map

Common migrant Western areas from Westland to Northland including most of the lowland North Island.

iNaturalist NZ
Observations map

Scientific Classification More info











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Also Known As;

Common Eggfly (Aust)


An eye-catching butterfly often seen on the west coast from March to May, sometimes into winter in sheltered spots. They are usually seen in New Zealand when there are large southwards migrations in Australia. In years when sizable numbers come to New Zealand, then they are more likely to been seen east of the North Island ranges. Their foodplants are found in New Zealand, so this species could breed in here. But it has never being recorded breeding in the wild as yet through. However they are easy to breed on Lesser Joyweed (Alternanthera deniticulata) if you can find ovum or larvae! They are native to India, South-East Asia, Pacific Islands and Australia. The New Zealand name comes from the blue dots on its forewings which are refractive, so the blue varies on the angle you see them.

Ovum  In English

Laid on the underside of the leaves in batches. Initially yellow, turning to green in colour and with vertical ribs.

Larvae  In English

Dark green with shiny black head at first, but later becomes dark brown with a yellow lateral stripe along sides and branched orange setae. It's head becomes orange-brown with 2 long spines. Remain living in a small group until the 3rd instar. Grows up to 65mm when fully grown.

Pupa  In English

Brown fattish pupa with darker mottling. Hangs by the cremaster from the foodplant. They are slightly larger than the Red and Yellow Admiral at 21mm. It has pointed spines on the abdomen.

Imago  In English

The imago has a 85-110mm wingspan. The female is larger, has red patches and more white on its wings. There are 3 forms of the female which have varying amounts of orange-red on the upper wing surface. The male has blacker wings then the females dark brown wings. Males and most females have an area of refractive purplish around their spots.


In Australia it is a woodland species that generally stays close to their foodplants in Australia, but will follow water courses south in high rainfall. In New Zealand they are more likely to be seen in any lowland area.

Food Plants

Lesser Joyweed (Alternanthera deniticulata), Paddy's Lucerne (Sida spp), Pigweed (Portulaca spp) and (Synedrella). It has also being recorded on Asytasia scandens, Pseuderanthemum variable and Ruellia.

Lifecycle of the Blue Moon

Contents > Butterflies > Migrant > Blue Moon