In 2011, the two smallest frogs in the world were discovered in Papua New Guinea. Paedophryne dekot and P. verrucosa, are only approximately 8.5 to 9 millimeters and 8.8 to 9.3 millimeters long, respectively and were identified by zoologist, Fred Krause of the Bishop Museum in Hawaii. Their names derive from the Latin phrase: ‘full of warts,’ and ‘tiny’ from the local Daga language.
Krause spotted the tiny tetrapods (vertebrates with four legs) when he was herping (hunting for reptiles or amphibians – see definition) on a side of a mountain, situates at the South Eastern side of Papua New Guinea.
Krause noted the ‘speck’ like creatures probably adapted to filled an important predator vacancy in the food chain of the region, where they adapted to exist on small insects such as tiny spiders and mites, found on the rainforest floor. However, he also speculated that predators of these diminutive tetrapods would also be insects; larger centipedes and spiders would be capable of predation of the two smallest frogs in the world.
Interestingly, both frogs share the same mountain but according to Krause, live at different heights. Both tiny frogs are varying hues of brown and black in color. 3 digits were observed on their front feet and four on their hind legs.
The smallest known vertebrate on Earth is Paedocypris progenetica, which was discovered and identified by ichthyologists, Tan Heok Hui and Swiss national, Maurice Kottelat from the Raffles Museum of Biodiversity Research and the National University of Singapore in 1996. Mature females, of the species only measure about 7.9 millimeters.
Fred Kraus, who has more than 30 years experience researching evolutionary biology and ecology in the Southwestern Pacific, Borneo, and the United States had previously identified Paedophyrne as a new genus of frog, which inhabits the rainforest floor.
The dedicated researcher initiated a program of field research on amphibians and reptiles in Papua New Guinea, leading 15 expeditions to 20 remote locations across the country which amazingly resulted in the discovery of 150 new species.
Kraus found the diminutive frogs Paedophryne dekot and P. verrucosa, by sorting through fallen leaves by hand and listening for their calls. Frogs are most easily found by tracking calling males at night. The frogs would spring from cover as fast as crickets which would make catching them by hand a difficult job.
The team wrote about their discovery and the real possibility of finding smaller frogs elsewhere in the Tropics in the ZooKeys December 11th, 2011 journal. They described the pair as having a, “long, strap-like tongue; and “continuous dorsolateral row of black blotches and flecks; sides and front and rear of thighs pale gray heavily flecked with dark brown.”
This species typically called at dusk, even continuing through the deafening period of cicada calling at approximately 1800–1830 h, but calling ceased soon after dark. It also frequently called before dawn, and occasional individuals were heard to call briefly in mid-morning. It was not heard by me to call on days lacking rain.
Team with Fred Kraus.
