The black grass-dart butterfly, native to NSW, has been added to the International Union for Conservation of Nature's list of endangered species.
A native NSW butterfly is under threat of extinction, according to a new report.
The black grass-dart butterfly has been listed as endangered on the International Union for Conservation of Nature's (IUCN) latest Red List, released in Sydney on Monday.
The insect is found only on the state's north coast, but part of its habitat has been destroyed by the "invasion of introduced weeds and coastal development".
"A significant proportion of its habitat exists in protected areas such as Bongil Bongil National Park and Gaagal Wonggan (South Beach) National Park," the report said.
The updated IUCN list now includes 76,199 plant and animal species - 22,413 of which are threatened with extinction.
That includes the Pacific Bluefin Tuna, which is now considered vulnerable because of the growing appetite for its use in sushi and sashimi.
The Chinese Pufferfish has also entered the list as critically endangered as its popularity rises in the Asian food market.