If a worm and a snake had a slimy, scandalous love child, it might look something like a caecilian: a legless creature that’s actually neither worm nor snake, but a soil-dwelling amphibian found in tropics across the globe.
Content to spend most of their time beneath the forest floor, caecilians are elusive and poorly understood. Which is why Carlos Jared, a biologist at the Butantan Institute in São Paulo, Brazil, has spent a good part of the last three decades hot on their trail.
Bagging a caecilian specimen, he said, often takes hours of laborious digging, carefully executed so a poorly aimed shovel doesn’t cleave the creature in two. Once a specimen is spotted, “you have to jump on it,” Dr. Jared said, and then wrestle the wriggly amphibian — which, depending on the species, can range in length from a couple inches to five feet — into a sack. Many caecilians have squirmed out of Dr. Jared’s grasp at the last moment, gleefully greased by a gelatinous goo that oozes out of their skin.
But Dr. Jared said the animals’ fascinating and sometimes baffling biology makes the incessant chasing more than worth it. His team’s latest discovery, published Friday in iScience, shows caecilians’ mouths might be rimmed by venom-tipped teeth, not unlike those found in some snakes.