Amateurs discover rare SA daisy

South Australia's 5000th native plant - a type of daisy - has been discovered by pair of amateur naturalists.

Trudie Jaques and Tony Lewis found the pleated daisy recently in the Innes National Park on the tip of Yorke Peninsula.

It was officially identified by the South Australian herbarium and given the scientific name podolepis rugata subspecies trullata, chief botanist Michelle Waycott says.