Introduction
The genus Vanessa comprises of about 20 species worldwide. The genus is divided into 2 groups – the Painted Ladies and the Red Admirals.
The Red Admiral group includes atalanta which occurs in Europe, Asia, north Africa and throughout North America; indica which is found in temperate regions of Asia; gonerilla from New Zealand, and the Yellow Admiral itea ( incorrectly placed in another genus Bassaris by some workers ) which is found in Australia and New Zealand, and also on Loyalty Island and Norfolk Island.
Vanessa gonerilla is endemic to New Zealand and is found on both islands.
Habitats
This species is very widespread in New Zealand and can be found in almost any habitat where the larval foodplants grow, and there are nectar sources available for the adults.
Lifecycle
The egg is green with 9 prominent vertical keels. It is laid singly on or near the stem of a stinging nettle Urtica dioica or on a leaf stalk of the nettle tree Urtica ferox. The larva lives solitarily within a shelter made by folding over a nettle leaf and fastening it with a few strands of silk. The fully grown larva is black and has branched dorsal and lateral spikes on each segment. There is a pale yellow zig-zag stripe below the spiracles, interrupted on each segment by a reddish spike. There are also thinner pale yellow dorsal and subdorsal stripes. The pupa is straw coloured, mottled with pale brown or dark purplish brown. It is suspended by the cremaster from a stem of nettle or a nearby twig or plant stalk.
Adult behaviour
Vanessa gonerilla is a fairly common butterfly but its numbers have decreased in recent decades, possibly as a result of the introduction of Pteromalus puparum, a parasitoid wasp imported from Europe to control the Large White butterfly Pieris brassicae. Males commonly bask on the ground, waiting to fly up and intercept passing females. Both sexes visit a wide variety of nectar sources, and visit sap runs on trees.