A rare Panamanian tree frog, a rodent from Madagascar and two lizards found only in the Philippines are among over 17,000 species threatened with extinction, a leading environmental group said Tuesday.

The Rabb's fringe-limbed tree frog, only discovered four years ago, is one of 1,895 amphibian species that could soon disappear from the wild because of deforestation and infection, the International Union for Conservation of Nature said.

The Switzerland-based group surveyed 47,677 animals and plants for this year's "Red List" of endangered species, determining that 17,291 of them are at risk of extinction.

More than one in five of all known mammals, over a quarter of reptiles and 70 percent of plants are under threat, according to the survey, which featured over 2,800 new species compared with 2008.

"These results are just the tip of the iceberg," said Craig Hilton-Taylor, who manages the list. He said many more species that have yet to be assessed could also be under serious threat.

The only mammal added to the list this year was the Eastern Voalavo, a rodent that lives in the mountainous forests of Madagascar. IUCN classified it as "endangered" - two steps from extinction in the wild - because its habitat is being destroyed by slash-and-burn farming.

The Red List already includes species such as the tiger, of which only 3,200 are thought to exist in the wild and whose habitat in Asia is steadily shrinking due to encroachment by humans. Governments and international conservation bodies use the list as guidance when deciding which species to place under legal protection.