Monarch Butterfly NZ Trust

Above photograph thanks to Nigel Venters.

Photo below thanks to Norm Twigge.

Note: The periods for each stage of development are based on summer temperatures.

This information was compiled by Norm Twigge, norm@monarch.org.nz

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Lepidoptera

Superfamily

Papilionoidea

Family

Nymphalidae

Sub-family

Nymphalinae

Tribe

.

Genus

Bassaris

Species

itea

Description

Adult butterfly approximately the size of a cabbage white butterfly. Black and brown on all four wings. Broad yellow bar on the forewings with white spots near the apex of the forewings. Hindwings are predominantly rust-brown with four small blue spots ringed with black at the lower edge of each hindwing. Underside of the wings is a cryptic brown, with a yellow bar and a blue eyespot at the top of the forewing.

Abundance

Reasonably common.

Distribution

Australia, New Zealand, and oceanic islands.

Reproduction

A period of active chasing precedes the mating of the sexes, usually during late afternoon/early evening. Ovipositing usually follows after 24 hours.

Male/female

There is no colouration or wing marking differences between sexes.

Host plant(s)

Will utilise all species of Urticacae (nettles)

Egg

Greenish with vertical ribs. Hatches after 8-9 days. Approximate size is less than 1mm diameter.

Larva

Can be extremely varied in its colouring. Often light brown or greenish underneath. Black, grey, brown, or intermediate shades above the lateral line. Spiny hairs along its back are noticeable as it grows. The final instar reaches about 36mm in length. Typically the larva will pull the edges of the leaf together with silk to create a tent in which to shelter, creating some means of protection from predators. Larval stage about 6-7 weeks.

Pupa

An irregular-shaped pale brown pupa some 15-20mm in length. Sometimes with gold patches, and occasionally the complete pupa is a metallic gold.

Metamorphosis - Adult

Emerges after 12-14 days.

Predators

Praying mantis, wasps, soldier bug, and spiders.

Parasites

The Australian self-introduced white spotted Ichneumon wasp (Echthromorpha intricatoria) and the introduced Pteromalid wasp (Pteromalus puparum) both infect the pupae.

Interesting notes

Pteromalus puparum was introduced by government entomologists in 1932-1933 in an attempt to control the spread of the cabbage white butterfly.

References

Butterflies of New Zealand – G Gibbs; New Zealand Insects and Their Story – R Scharell; Butterflies of Australia – IFB Common & DF Waterhouse.