Austroperla cyrene
In 3 days ~30% in a week ~50%
Austroperla cyrene, the black stonefly, is a species of austroperlid stonefly endemic to New Zealand. It is the single species in the genus Austroperla. The species is a 'shredder' that lives and feeds on decomposing wood and leaves in streams throughout New Zealand. It is particularly common in forested streams but relatively rare or absent from deforested streams.
A. cyrene nymphs and adults contain hydrogen cyanide and as a result are toxic to predators. To advertise their toxicity, A. cyrene adults have striking aposematic (warning) colouration, with bright yellow and white colour features against a black background.
This distinctive warning coloration is mimicked by melanic specimens of the non-toxic stoneflies Zelandoperla fenestrata and Taraperla pseudocyrene. A fossilised specimen of Austroperla has been recorded from early Miocene sediments of Foulden Maar in Central Otago. A phylogenetic study of Southern Hemisphere stoneflies similarly suggests an ancient history for this New Zealand lineage, with Austroperla estimated to have diverged from Australian and Chilean austroperlids around 37 million years ago. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Egmont National Park | 🇳🇿 New Zealand | |
| 2 | Fiordland National Park | 🇳🇿 New Zealand |
With luck
About 10% of wildlife watchers report a Black Stonefly sighting in Egmont National Park on a given day, based on 8 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 79th most-seen of the 191 insects we can rate there. Over three days the chance rises to about 30%, and over a week to about 50%, if each day is a fresh chance.
October to December
In those months about 20% of wildlife watchers report a Black Stonefly in Egmont National Park on a given day, against under 5% in April to September, the lowest months.
Between 1 and 4 pm
Across all the parks we cover, that three-hour window holds the most Black Stonefly sightings with a recorded time, and about 6 in 10 of them come between 6 am and 6 pm: it is seen both by day and at night.
Yes
Of the 2 parks where we can rate Black Stonefly sightings, Egmont National Park has the highest daily chance: about 10%. Next come Fiordland National Park (New Zealand, about 10%).
GBIF citizen-science records
It is estimated from how often the Black Stonefly is recorded against all the insects logged in Egmont National Park (8 verified sightings from 2019 to 2026), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
