September 29, 2017

The region of the Western Ghats mountain range in India has turned up another new species of frog in 2017, and this one is quite bizarre. Bhupathy’s purple frog was named in honor of noted herpetologist Subramaniam Bhupathy, who died from a fall during an expedition in the Western Ghats in 2014. Herpetology is the branch of zoology concerned with the study of reptiles and amphibians. Bhupathy’s purple frog is rather stout with shiny purple skin, small eyes ringed with light blue, and a pointy piglike nose.

The unusual and newly discovered Bhupathy’s purple frog surfaces only during monsoon (and mating) season. Credit: © Jegath Janani, Alytes

You may recall a Behind the Headlines entry from earlier this year describing seven tiny new frogs also found in the Western Ghats region. Seven at one time is astounding, but it may be an even greater feat to have discovered this single amphibian. You see, Bhupathy’s purple pig-nose frog lives almost entirely underground and has only one other member in its frog genus Nasikabatrachus. Elizabeth Prendini, a herpetologist at the American Museum of Natural History in New York City, co-wrote a paper describing the species in a recent issue of the batrachology (study of amphibians) journal Alytes.

Bhupathy’s purple frog looks bizarre, to be sure, but it also has a bizarre life cycle. The only time an adult frog emerges from of its underground home is during the monsoon season. The reason for this excursion is to mate. When the rainy season begins, the male purple pig-nose frog calls from underground and is lured into the open by the presence of an interested female. After frog negotiations are complete, the frogs mate in a stream, leaving behind fertilized eggs. The frog parents then go their own ways and crawl back beneath the soil. After the tadpoles hatch, they move from the streams to cliffs behind waterfalls, where they cling to rocks using suckerlike mouths, devouring the algae that grow there. After several weeks, the tadpoles develop into adult frogs and drop from the waterfall cliffs. They then find a suitable place to make their underground home, where they live the rest of their lives—except to mate, of course, during the rainy season. Bhupathy’s purple frogs do not even surface to eat. They use their long, fluted tongues to eat subterranean termites and ants.

Bhupathy’s purple pig-nose frogs may be unlike any others, but like most frogs, unfortunately, they are endangered. One-third of the frogs in the Western Ghats region are threatened with extinction. Increased conservation efforts are needed to protect these new species as well as other frogs from threats posed by habitat loss, pollution, and climate change.

August 25, 2017

The Andes Mountains of Peru in South America have recently revealed some grape-sized secrets: three new species of so-called rubber frogs. An international team of researchers discovered the tiny amphibians while rooting through the Andean grass, rocks, and moss, and the scientists published their findings last month in the journal Zootaxa. The team, which consists of Edgar Lehr from Illinois Wesleyan University, Rudolph von May from the University of Michigan, and scientists from Peru and the Czech Republic, has been rather frog happy lately. The newly described animals—the Pui Pui rubber frog, Humboldt’s rubber frog, and the hill dweller rubber frog—are actually the third, fourth, and fifth new frog species discovered by the team this year. The species discovered earlier, which are also found in the Peruvian Andes, are Attenborough’s rubber frog and the Ashaninka rubber frog.

Humboldt’s rubber frog is found only at a single site high in the Andes Mountains of Peru. The frog is named for German naturalist and explorer Alexander von Humboldt. Credit: © Rudolf von May, University of Michigan

To make these discoveries, the scientists ventured to the hard-to-reach Pui Pui Protected Forest in Peru, a two-day hike from the nearest human settlement. The remote protected area, established in 1985, consists of alpine forests and grasslands. There have been few biological surveys conducted in the park since it was established, which leaves the possibility of more animal discoveries in the future.

The tiny hill dweller rubber frog lives among the bushes, mosses, trees, and feather grass of the Peruvian Andes. Credit: © Rudolf von May, University of Michigan

The three new species are land-breeding frogs, and they do not have a tadpole stage. The eggs laid by females develop directly into froglets. This mode of reproduction is successful as long as there is plenty of moisture.

Like all frogs, these new species are faced with threats from habitat loss and climate change, as well as Chytrid fungus, which can lead to chytridiomycosis, an infectious disease that has depleted amphibian populations around the world. The scientists took skin samples from the frogs, and several had the fungus—but that does not necessarily mean the frogs have the deadly disease. It is important to know that the fungus is there, however, so scientists can learn how these isolated frogs react to it.

July 28, 2017

It is common these days for people to reverse traditional gender roles. In the animal kingdom, however, it is a rare thing for males and females to switch traditional roles. Sex-role reversal in the animal kingdom has been observed only in seahorses and pipefishes, giant water bugs, and jacana and phalarope birds. Recently, however, scientists added another animal to the short gender role reversal list: the smooth guardian frog (Limnonectes palavanensis) of Borneo, a large island in the South China Sea.

Seahorses are one of the few animals that exhibit traditional gender role reversal. A female seahorse lays her eggs in a pouch on the male. The male then carries the eggs until they are ready to hatch. Credit: © Frolova_Elena/Shutterstock

In June 2017, scientists reported in the journal Behavioral Ecology and Sociobiology that female smooth guardian frogs have been discovered serenading males in an attempt to win them over—a reversal of most animal mating rituals. These frog females, like so many lovesick Juliets, sing to woo their amphibian Romeos. In response, a male sings out with a call to let the female know if he is available. Then, if the mating is successful, the male sticks around and tends the eggs for 9 to 11 days. After the eggs hatch, the male carries the tadpoles on its back to suitable pools of water where the tadpoles will grow and mature into adult frogs. The study also found that male smooth guardian frogs do not defend their territory and do not have an aggressive call to ward off predators—a task left to the serenading and wooing Juliets of the species.

Most other frogs operate in the opposite manner. Male frogs will enter a pool of water and then call to attract mates. Their call also directs other males to the water, who assume it is a suitable spot for mating. If all goes well, then, the female frogs watch over the eggs and newly hatched tadpoles. Usually, too, male frogs bark to scare off unwanted guests around the lily pad.