Mount Kaputar in Australia is the only known home of a bright pink species of slug.

Mount Kaputar in Australia is the only known home of a bright pink species of slug, notes National Geographic. 
Michael Murphy, a long-time park ranger for that area, is quoted in the Sydney Morning Herald as saying that the slugs “are buried in the leaf mould during the day, but sometimes at night they come out in...hundreds and feed off the mould and moss on the trees.”
Murphy also hypothesized that their distinctive color could be camouflage for their time spent among red eucalyptus leaves, or he admits, it could simply be a “quirk of evolution.”  
Their primary habitat is a six-square-mile forest atop the mountain, reports Atlas Obscura.
This section is believed to be a holdover from the time when Australia was part of a larger landmass called Gondwana and had a more tropical climate.
Experts suspect that an eruption of Mount Kaputar 17 million years ago resulted in the isolated area retaining its original lushness. 
The hot pink slug was identified as a unique species around 2013.