Scientists from Newcastle University, the Australian Museum, the South Australian Museum and Queensland National Parks and Wildlife have found and described two new species of very noisy frogs from eastern Australia: the slender bleating tree frog, Litoria balatus and the howling tree frog, Litoria quiritatus.
Posted today in Zootaxa, the newly described slender bleating tree frog occurs in Queensland, while the howling tree frog occurs from around Taree in NSW to just over the border at Victoria.
Scientifically described with the help of Citizen Scientists and their records via the Australian Museum’s FrogID app, the new frog species were once thought to be a single species, the bleating tree frog, Litoria dentata.
Australian Museum herpetologist and lead scientist for the breakthrough FrogID project, Dr Jodi Rowley, said the bleating tree frog is well known to residents of Australia’s east coast for its extremely loud, piercing and almost painful call.
âThese noisy frog singles are very loud when they try to woo their mates,â Rowley said.
Scientists analyzed numerous calls submitted to the FrogID project across Queensland and New South Wales to differentiate the calls.
âOur review found that their calls differ slightly in terms of duration, treble and speed of fire. The slender tree frog has the shortest, fastest, and highest-pitched calls, âRowley explained.
Slender Bleating Frog (HB Hines)
Chief Scientist of Evolutionary Biology, South Australian Museum, Professor Steven Donnellan said genetic work was the first clue that there are in fact three species.
“Although similar in appearance and in their screeches, frogs are genetically very different. I am still amazed that it took us so long to discover that Australia’s loudest frog is not one but three species. “Said Professor Donnellan.
“How many other species not described in the ‘silent director’ category are waiting for their scientific debut? “
The three species vary subtly in appearance. The slender bleating tree frog, as the name suggests, is slender in appearance and has a white line extending down the side, and males have a distinctly black vocal sac.
The Howling Tree Frog is not as slender, does not have a white line extending to the side, and males have a bright yellow vocal sac. During the breeding season, the entire body of male Howling Frog also tends to turn lemon yellow.
The robust bleating tree frog is more similar in appearance to the howling tree frog, but males have a brownish vocal sac that turns dull yellow or yellowish brown when fully swollen.
Professor Michel mahony from the School of Environmental and Life Sciences at Newcastle University – who over the course of his long career has developed a cryopreservation method, the first genome bank for Australian frogs – said the three closely related species are relatively common and widespread.
“They are also all at least somewhat tolerant of modified environments, being recorded as part of the FrogID project relatively often in backyards and enclosures, as well as in more natural habitats,” said Prof Mahony.
Dr Rowley noted that these new frog species bring the total number of known native frog species of Australia to 246, including recently recognized species. Gurrumul’s Toadlet and the Frog in pocket Wollumbin.
âThe research and help from our citizen scientists highlights the valuable contribution anyone can make to better understand and conserve our frogs,â Rowley said.