The endangered purple copper butterfly (Paralucia spinifera) is only known to occur in the Central Tablelands of New South Wales, around Bathurst, Oberon and Lithgow.
This species was identified by scientists in 2021 as one of 26 Australian butterflies at greatest risk of extinction. We don’t know exactly how many individuals remain, but it is possible that more populations will be identified where the butterfly’s food plant occurs. These may lie outside the species' currently known distribution.
Purple copper butterflies are important pollinators and play a valuable role in food chains. The species has a mutualistic relationship with the ant Anonychomyrma itinerans, which protects caterpillars from predators in return for a sugary honeydew produced by the caterpillars. As herbivores, the caterpillars eat the leaves of plants and cycle nutrients back into the soil through their faeces. They also serve as food for animals such as birds, spiders, dragonflies, flies and wasps.
Without urgent conservation action, this species is at risk of extinction. At Saving our Species, we are committed to securing threatened species. Let’s take a closer look at this rare and endangered butterfly, what’s being done to save it and how we can all help.
An update on the purple copper butterfly conservation project
Threats to the purple copper butterfly include habitat loss and modification through clearing, spraying, grazing, inappropriate use of fire, weed invasion and habitat disturbance by feral pigs.
Under the Saving our Species program, the NSW Government is funding several actions to conserve the butterfly, including:
- monitoring of butterfly populations at known sites
- surveys to help find more butterflies
- pest and weed control
- community engagement so people can keep a look out and report any sightings
- ecological burns to ensure healthy habitat for the butterfly.
About the purple copper butterfly
What does it look like?
The purple copper butterfly is a small butterfly with a thick body and a wingspan of only 20–30 mm. The upper sides of its wings are purple, black or deep brown, with a bronze or green iridescence in sunlight. The undersides of its wings are patterned with subtle brown, black and grey. Its black antennae are dotted with white spots and have a black tip.
Butterflies can emerge from late August through to early November and they usually fly between 10 am and 2 pm on warm sunny days with little or no wind.
Adult males fly rapidly at about one metre from the ground and rest in the sun with their wings parted. Females fly less rapidly and tend to stay closer to the host plant, a native blackthorn shrub, on which they lay their eggs. Typical behaviours include territorial chasing and spiralling courtship chases, with one female being pursued by several males. They also like to perch in the sun and feed on nearby flowers.
Caterpillars grow to about 22 mm in length and are light green with darker longitudinal markings. They are nocturnal and can be found crawling along the blackthorn stems and feeding on the leaves from 10 pm to 5 am between November and January. They will be attended by between one and 15 ants, with other ants patrolling a line between the feeding caterpillar and the ant nest at the base of the plant. Ants also roam around the host plant and will attack other insects.
The purple copper butterfly is one of Australia’s rarest butterfly species. 
When the larvae (caterpillars) hatch, they are immediately tended by ants. 
The purple copper butterfly has a wingspan of 20–30 mm. 
Native blackthorn is the only food plant of the purple copper butterfly larvae (caterpillar). 
Viewing the underside of the wing assists with identification of purple copper butterflies. 
The purple copper butterfly lives in open woodland or open forest with a sparse understorey that is dominated by the shrub native blackthorn. 
Native blackthorn is a multi-stemmed shrub with small, dark-green leaves and thorns/spurs. 
Butterflies emerge from late August to early November.
Where is it found?
The purple copper butterfly is found in the area bordered by Bathurst, Portland, Lithgow and Oberon in the Central Tablelands of New South Wales, with an outlying population at Mount David. It is also likely to occur in new areas yet to be discovered across New South Wales. It is one of Australia’s rarest butterfly species.
The following features are common to known sites:
- altitude greater than 850 m above sea level
- presence of native blackthorn (Bursaria spinosa subsp. lasiophylla)
- presence of attendant ant (Anonychomyrma itinerans)
- heavy frosts and/or occasional snow
- 3–4 hours of exposure to direct spring sunlight.
What is its habitat?
The purple copper butterfly lives in open woodland or open forest with a sparse understorey that is dominated by the shrub native blackthorn – Bursaria spinosa subsp. lasiophylla.
Native blackthorn is the only food plant of the purple copper butterfly larvae (caterpillar). The caterpillar’s distinctive grazing pattern is evident from October to May. Grazed native blackthorn will have leaf buds or small leaves replacing the grazed leaves; entire plants can be defoliated of mature foliage. Often, the stems are eaten from the ground up, as opposed to the grazing patterns of beetles that graze from the tips of the plant down. Conserving the small areas of blackthorn that remain is critical to saving the butterfly from extinction.
Native blackthorn is an erect, spindly, often multi-stemmed shrub that generally grows to approximately 2 metres tall. It has spines along the primary branches and the dark green foliage is sometimes sparse.
It is most obvious in spring to summer when mass flowering occurs on the outer branches. The small white to cream flowers have a strong fragrant perfume that attracts a range of insect pollinators.
Blackthorn grows at high elevation sites on heavier clay soils, in eucalypt woodlands throughout south-eastern Australia. In the NSW Central Tablelands, stands of blackthorn occur in remnant woodland areas along roadsides, on different public lands and on private property.
What is its life cycle?
The butterfly’s life cycle relies on a ‘mutualistic’ relationship with the ant (A. itinerans) and the presence of native blackthorn. After mating, the female lays her eggs on or near blackthorn bushes, at the base of which there are nests of the attendant ants. During the 14 to 17 days the caterpillars take to hatch, the attendant ants constantly patrol the blackthorn. When the larvae hatch, they are immediately tended by ants.
As the caterpillars grow, the ants move them underground into their nest during the day and out at night to continue grazing on the native blackthorn leaves. The ants’ efforts are rewarded with a sugary honeydew from a gland on the caterpillar’s back. Pupation (the transformation from caterpillar to butterfly) occurs between December and August within the underground ants' nest.
How you can help
Counting Coppers: join the search for the purple copper butterfly
The Saving our Species program is seeking volunteers to help search for the endangered purple copper butterfly this spring.
People living in or visiting Bathurst, Oberon, Lithgow and nearby areas are invited to be part of a vital mission to search for and protect the region’s endangered purple copper butterfly.
Participating in the search and reporting sightings will provide the Saving our Species team with valuable data that will aid in the protection of this endangered butterfly.
You can report sightings of purple copper butterflies via NatureMapr or by emailing Saving our Species.
Tips to help you with your search
- The ‘flying season’ for purple copper butterflies spans from late August to early November. Butterfly activity peaks in September and October at most sites.
- Butterflies are best spotted on sunny, calm days between 10 am and 2 pm.
- They are most active when the temperature is above 15°C and cloud cover and wind are low or absent.
- When butterflies are disturbed, they’ll briefly take flight, so take your time walking through the habitat and watch for movement.
- After taking flight, butterflies will often land in the sun to bask. Avoid casting a shadow on the butterfly – now is your chance to get up close and take some photos.
- They only live at elevations above 850 m, where their food plant native blackthorn is found.
- Native blackthorn (Bursaria spinosa subspecies lasiophylla) is the only food plant that purple copper butterfly caterpillars eat, but adult butterflies can be found feeding on other flowering plants.
Observations to take note of
- Where they are sighted; take a GPS location if possible – you can do this by saving a location in your phone’s map application
- Time and date of your sighting
- What habitat they are using; take note of the vegetation in the area if you are able to identify any plants or trees
- How many individuals are sighted
- Photos are extremely useful for confirming identifications; take photos of the upper wing and underwing of butterflies where possible.
How to report a sighting
- Record your sighting through NatureMapr. You’ll need to register for an account through your smartphone, tablet or web browser.
- Sightings can also be reported by emailing [email protected]. Remember to include photos (top-of-wing and underwing photos where possible), the sighting location and number of butterflies sighted.
- Participating in the search and reporting sightings will provide the Saving our Species team with valuable data that will aid in the protection of this endangered butterfly.
Acknowledgements
The purple copper butterfly conservation project is led by the Saving our Species program in partnership with:
- Central Tablelands Local Land Services
- Lithgow City Council
- Lithgow Oberon Landcare Association
- NSW National Parks and Wildlife Service
- private landholders.