The green, volcanic landscapes of Sulawesi, Indonesia are home to a wide range of toothed frog species, some with unique reproductive behaviors. Among them is Limnonectes larvaepartus, the one frog known worldwide for giving birth to live tadpoles. Revealing one other secret, this tropical island now features the world’s smallest fanged frog.
The recently identified Limnonectes phyllofolia, related to other fanged frog species, is consistent with the normal amphibian egg-laying method. A gaggle of herpetologists from the United States and Indonesia were climbing through the rainforest once they got here across a particular sight: leaves and mossy boulders rising several feet above the bottom, containing glassy, black frog eggs.
This immediately intrigued researchers because frog eggs typically need water to forestall their gelatinous coating from drying out. Shortly thereafter, they spotted spotted, brown frogs the scale of a dime guarding their nests. Lead creator Jeff Frederick, a wildlife ecologist on the Field Museum in Chicago, noted: “Typically, once we search for frogs, we give attention to stream banks or wade through streams to identify them directly within the water.”
However, their commentary of frogs tending leaf nests was different from the norm. These guardian frogs coat their eggs with substances that retain moisture and protect against bacteria and fungi. Surprisingly, all the frogs on the event were male. Frederick noted, “Although males protecting eggs isn’t unusual in frogs, it is comparatively rare.”
This newly discovered frog species showed tiny teeth on the upper jaw and two small fangs on the lower jaw, an unusual feature because frogs typically only have teeth on the upper jaw. Frederick emphasized: “Compared to other fanged frogs on the island, this latest species is small.”
Although there are larger saber-toothed frogs in Sulawesi, this latest species weighs only about two grams, or in regards to the same as a penny. It gained the nickname Limnonectes phyllofolia, derived from the “leaf nester”.
In Southeast Asia, many frog species have developed fangs to enable territorial battles, mating, and hunting prey reminiscent of centipedes and crabs. Leaf-nesting frogs that don’t rely upon waterways for replica may not need large fangs to compete in crowded streams for optimal egg-laying sites. This could explain the smaller size of the fangs in comparison with other island frogs, because the researchers hypothesized.
Previous research has shown that frog fangs evolve independently at the very least 4 times in all frog species. Examination of the behavior and weight loss plan of those species suggests that frog fangs that evolve consequently of sexual selection are likely to be relatively larger than people who develop consequently of other environmental pressures.
Toothed frogs have been discovered in Cambodia, Vietnam, West Africa and South America. Scientists have also identified tadpoles with fangs from the flying vampire frog (Rhacophorus vampyrus) in the luxurious evergreen forests of southern Vietnam
