Tuesday, March 6, 2012
They aren't worms or even snakes. They're soil-burrowing, limblessamphibians, and they're completely new to science, a new study suggests.
Pictured guarding a brood of eggs in its native northeastern India, the animal above is one of about six potentially new species belonging to a mysterious group of animals called caecilians. What's more, the newfound critters represent an entirely new family of amphibians—family being the next major level up from genus and species in scientific naming conventions—according to findings announced today by the journal Proceedings of the Royal Society B.
Christened Chikilidae ("Chikila" being a local tribal name for caecilians), the family's closest relatives live more than 7,000 miles (11,265 kilometers) away in tropical Africa, the study team reported.
A previously unknown caecilian from India watches over her clutch of eggs in the lab of University of Delhi amphibian biologist Sathyabhama Das Biju.
Biju and his team were surprised to discover that females of this newly named species, Chikila fulleri, remained protectively coiled around their developing offspring for up to three months.
"The mother is guarding the eggs for almost 95 days without eating anything," Biju said. "Always the mother is with her eggs."
Such levels of maternal care are rarely seen in amphibians, the study team noted.
A 3-D skull reconstruction based on CT scans reveals telltale features to scientists who have now assigned up to half a dozen newfound caecilian species from India their own separate family.
Tiny distinctions in the jaw, nose, and eye structures of the snakelike amphibians show the new family belongs to an ancient lineage whose nearest relatives live in Africa, the study team said.
DNA evidence indicates that the Indian group split off from other caecilians more than 140 million years ago.
The embryo of a newly discovered caecilian species, Chikila fulleri, is revealed in microscopic detail inside its translucent egg.
Also visible is the embryo's white yolk supply, which provides the legless amphibian enough nourishment to emerge from its egg as a miniature adult (most amphibians go through a tadpole-like, swimming stage in their early development).
Some young caecilians are known to feast on their mother's skin after hatching. Such behavior has yet to be observed in the newfound Indian species, however.