Monarch Butterfly NZ Trust

Above photograph kindly supplied by Nigel Venters (Argentina).

Nigel is a lepidopterist who says the NZ Red Admiral is the ‘best in the world’.

Below: Photo supplied by Terry Smithers.

Our own very beautiful Red Admiral, thanks to Terry Smithers for photograph

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

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Lepidoptera

Superfamily

Papilionoidea

Family

Nymphalidae

Sub-family

Nymphalinae

Genus

Bassaris (sometimes Vanessa)

Species

gonerilla

Description

Adult butterfly with a wingspan of 50-60 mm. Predominantly dark brown or black with patches of red on both upper surfaces of the forewing and hindwing. The tip of each forewing has minor white spots. The red patch on each of the hindwings has four blue eyespots ringed with black. The under surface of the wings is a cryptic brown, with the forewing having red and yellow patches, with a blue eyespot. Various Red admiral butterflies occur worldwide (genus Vanessa) but lack the blue centred eyespots of our NZ endemic, one of the reasons for placing it in a different genus (Bassaris). Two subspecies exist, the mainland species Bassaris gonerilla gonerilla, and B. gonerilla ida, which is found only on the Chatham Islands. Minor wing marking differentiates the two species.

Abundance

Reasonably common.

Distribution

Endemic to New Zealand and near offshore islands, and the Chatham 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)

The endemic nettles Urtica ferox (Ongaonga or tree nettle) and U. incisa are listed as being the main host plants, but the introduced nettles U. dioica and U. urens are also utilised.

Egg

Dark green with vertical ribs. Hatches after 8-9 days. Pinhead size.

Larva

The colour varies from velvety black in some specimens through pale brown to reddish-brown, always paler underneath. Usually light brown or greenish beneath the lateral stripe. Spiny hairs 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 dull brown or greyish pupa some 15-20 mm in length, with metallic gold on the raised knobs.

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 infects 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. Compiled by Norm Twigge, norm@monarch.org.nz