SYDNEY, May 22 (Xinhua) -- Researchers in Australia have discovered two new lizard species on Wednesday, however one of them might already be extinct.

Set up by a National Recovery Team from the Department of Environment, the year-long project wanted to find out if the Grassland Earless Dragon from south-eastern Australia was one single species.

"Over the last year, I've been working with them and researchers at the University of Canberra, and we've been looking at the genetics and the morphology of the lizards," author of the study Dr Jane Melville from Museum Victoria told Xinhua on Wednesday.

"What we've discovered is that it's not one single species, but it's in fact four species."

A tiny green, brown and yellow patterned lizard weighing only about eight grams, Melville compared the genetics of historic specimens at the state museum which were collected in the late 1800's, against samples that found recently in areas across Victoria, New South Wales and the Australian Capital Territory.

"They've developed some ingenious ways of catching them," Melville said.

"These lizards hide in spider burrows and out in the grassland there are big wolf spiders, so one of the ways researchers catch them is to make artificial spider burrows in the ground and when they come back they will check if there is a little lizard in there."

While the discovery should give conservationists a much better understanding of how to protect the creatures, one of the new species categorized has not been sighted since 1969, sparking fears it may be the first ever reptile to become extinct on the Australian mainland.

With researchers now trying desperately to locate the species, Melville said "I'm optimistic. I really hope they find it."