On the night of 2 March 2024, at the South Sea Hotel in Oban on Stewart Island, Pav Johnsson, a Swedish bird watcher and enthusiastic lepidopterist, became the only known living person to see the frosted phoenix moth (Titanomis sisyrota).
A frosted phoenix moth (Titanomis sisyrota) photographed on Stewart Island by Pav Johnsson on 2 March 2024. Photo reproduced with permission from Pav Johnsson. All rights reserved.
Prior to this historic night, the frosted phoenix was only known from 10 reliable reports and eight specimens held in natural science collections—it had not been seen or collected for 65 years. The moth is so rare, in fact, that the Department of Conservation listed it as data deficient and potentially extinct. Then Pav Johnsson took a holiday on Stewart Island.
One evening, before setting off on a walk to try and find some kiwi, Pav set up a small UV lamp on the balcony at his hotel. Upon returning, he photographed the handful of moths that had been attracted to the lamp with his cellphone camera and went to bed, completely unaware that one of these nocturnal visitors had not been seen since 1959.
After heading back to Sweden, Pav tried to identify the moths he had photographed and couldn’t figure out one of them. He uploaded his images to iNaturalistNZ and, in doing so, made the most significant single contribution since the website’s inception. It was equivalent to the rediscovery of the takahē in the Murchison Mountains in 1948.
Several of New Zealand’s best taxonomists very quickly provided identifications, including Dr. Robert Hoare from Manaaki Whenua Landcare Research, who is New Zealand’s top Lepidoptera taxonomist. Dr. Hoare said on the identification of the moth:
“This is the greatest Lepidoptera find in the history of iNaturalistNZ.
No other living soul has seen this moth, the Holy Grail of NZ moths. It was last seen in 1959 and at one time was believed extinct, but I always thought there was hope. The enigma is enhanced by the fact that the family placement of the moth is unknown, but it may belong somewhere in the region of Cossidae.
Truly astonishing! Never recorded from Stewart Island before, but there is a 1900 specimen from Haldane, Southland not so far away. This is the 11th individual ever seen.”
Titanomis sisyrota is the only moth in its genus, and its relationship to other moths is not well understood. Very little is known about its lifecycle, including where the larvae live or what they eat. What we do know is that adults are on the wing from December till March and, from its limited number of sightings, that the frosted phoenix can be seen from the Waikato to Stewart Island.
The moth itself can be described as brownish-grey with darker spots and white scales on the margins of the wings. It is approximately 3.5 cm long and has a wingspread of 7 cm.
Female specimen of Titanomis sisyrota from the New Zealand Arthropod Collection, photographed by Birgit E. Rhode, Landcare Research New Zealand Ltd. CC-BY 4.0.
You can see Pav Johnsson’s observation here: https://www.inaturalist.org/observations/202565126