The Purple Copper Butterfly, also known as the
Bathurst Copper Butterfly (
Paralucia spinifera), is one of
Australia's
rarest butterfly species and is listed as
Vulnerable on the Commonwealth and
New South Wales threatened species lists. It is a small butterfly with a thick body and a wingspan of only 20-30mm. The upper sides of its
wings are either a black or deep brown with a bronze or green when they are sunning. The undersides of its wings are brown, black and grey. The adult males will fly about one metre from the ground, and the females fly less rapidly and tend to stay closer to its host
plant.
The butterfly was first identified in 1964 near the village of Yetholme. It was not seen again until 1977 and finally described as a new species in 1978.(Which is why you will find different dates on different websites.) Its habitat includes 29 locations in the area around Oberon, Hartley and Bathurst. (NSW, Australia.) All these sites are about 900 metres elevation and receive about three to four hours exposure to direct sunlight in spring.
The butterfly's life cycle relies on a relationship with the ant species Anonychomyrma itinerans, which is restricted to regions about 900 metres elevation. The copper butterfly also relies on the native blackthorn species Bursaria spinosa, which is a spiney and multi-stemmed plant which rarely exceeds 2 metres in height, an altitudinal variant of the more widespread and common species. Given the reliance upon elevation of both the attendant ant and host plant, the distribution of the copper butterfly has always been restricted. Grazing of the host plant by sheep, goats and cattle, clearing for the establishment of pine plantations, invasion of exotic weeds and activities of feral pigs has lead to the decline of this butterfly. It is unlikely to colonise new areas after its habitat has been destroyed. The rarity of the purple copper also makes it attractive to collectors. This is thought to have contributed to severe population decline at one site.
After mating, the female lays her eggs on the blackthorn bushes near the nests of attendant ants. The eggs take between 14 to 17 days to hatch, with the attendant ants are constantly patrolling the blackthorn. When the larvae hatch and mature, the attendant ants carry them underground into their nests during the day, and taking them out at night to graze on the blackthorn leaves. This is thought to offer the larvae some protection from predators while they feed. In return, the ants receive nutritional, sugary honeydew from a gland on the larvae's backs. When the larvae are fully grown, they return to the ants nest to pupate from between December to late February, and come out as butterflies in the spring.
Conservation of the purple copper and its habitat requires more information about the butterfly and involvement from the local community. There is the purple copper butterfly recovery effort the informed support of habitat owners is the best protection most sites will achieve - but general community interest is also a vital element.
Sources and pictures:
http://www.nationalparks.nsw.gov.au/npws.nsf/Content/Purple+copper+butterfly/
http://www.nationalparks.nsw.gov.au/npws.nsf/Content/Bathurst+copper+butterfly+endangered+species+listing
http://www.ento.csiro.au/conservation/area_of_research/conservation_genetics/paralucia_spinifera.html