Rediscovered Borneo Rainbow Toad: After 87 Years, the Elusive Ansonia latidisca Returns

The Borneo Rainbow or Sambas Stream Toad, Ansonia latidisca, is known only from drawings made by its discoverer, and has not been seen in 87 years.  Extensive development of its only known habitat has long raised fears of its extinction.  This month (July, 2011), however, it became the second of the world’s “Ten Most Wanted” amphibians to be rediscovered.

“Ten Most Wanted”

In 2010, Conservation International launched the Global Search for Lost Amphibians (please see article below).  Since then, several very rare frogs and salamanders have been found, but the tiny Borneo Rainbow Toad has remained elusive.  In fact, only one of the 10 species granted highest priority (the Ten Most Wanted) had turned up – Ecuador’s Spotted Stubfoot Toad, Atelopus balios.  However, a 3-month-long search of the Gung Penrisser Mountains in Sarawak, western Borneo, revealed that the Rainbow Toad is still with us.

Finding a Long-Lost Amphibian

Prominent herpetologist Indraneil Das, whom I’ve had the pleasure of meeting at several conferences, led the search, which was held after nightfall among trees along high mountain ridges.  Despite being brilliantly clad in red, yellow, purple, black and green, the aptly named Rainbow Toad is a mere 2 inches in length, nocturnal, and lives above ground – not an easy creature to find.  But Dr. Das’ team prevailed, and 3 individuals were finally located in their arboreal hideaways.

An Uncertain Future

The Borneo Rainbow Toad is known from only two locations and likely has a tiny total range.  Unfortunately, most of its habitat has been converted to golf courses and farmland, and the only streams in which its tadpoles were once found are subject to runoff and heavy siltation.  Prospects for the creature’s future are dim, but conservation measures are being discussed.

Most missing and newly-discovered frogs are tiny, drab creatures that, unfortunately, excite only diehard amphibian enthusiasts.  The Borneo Rainbow Toad is, however, a beautiful little beast.  For this reason, the exact site of its rediscovery is being held in confidence, lest collectors move in.

Other Unusual “New” Frogs

Some surprisingly large and interesting amphibians have been found in recent years, including Thailand’s Bird Eating Frog and the world’s only known Lung-less Frog, a native of Borneo.