Smallest Snake In The World

When evolutionary biologist Blair Hedges went to Barbados in 2006, he found two tiny earthworm-like animals under a rock.

But they are not worms - actually he had discovered the smallest snakes in the world!















Prof. Hedges, who is a professor at Pennsylvania State University, noted that: "It's about as wide as a spaghetti noodle."

The newly found species, which has been named Leptotyphlops carlae after his wife, is only about 10 cm long when fully grown. It belongs to a genus of small snakes commonly called threadsnakes.

This discovery is significant because Leptotyphlops carlae may represent the lowest possible limit to the evolution of body size in snakes.

Large snakes tend to lay multiple eggs, and their offspring are about 10% of the adult length. On average each snake lays about seven eggs at a time (some species laying up to 100 eggs!)

In contrast, current evidence indicates that the Leptotyphlops carlae only produces one elongated egg in its body - it could be too small to produce any more. Offspring of threadsnakes are typically half the length of full-sized adults.

Having fewer offspring reduce the chances of survival to the next generation.

Prof. Hedges feels that the evolutionary tradeoff between the number and size of offspring has reached a size boundary in this species of snakes.

On the other hand, biologist Nathan Kley at Stony Brook University in New York, said it may be too soon to declare the Barbados thread snake the world's smallest, since several closely related species are only a few millimetres longer, and those species are known from only a few observations or museum specimens.

Prof. Hedges is aware of this.

"When you get down that small, every millimeter counts."

Sadly, the Leptotyphlops carlae may be on the verge of extinction. It appears to live on only a few square kilometers of forest on Barbados, where almost all the original forests have been cleared.

"I think it should be considered critically endangered because of its limited habitat, apparent rarity, and ongoing threats," Prof. Hedges added.


Would you like to know more?

About Leptotyphlops carlae:
- Original research article (PDF file): At the lower size limit in snakes: two new species of threadsnakes (Squamata: Leptotyphlopidae: Leptotyphlops) from the Lesser Antilles (Hedges 2008, Zootaxa)
- World's Smallest Snake Discovered, Study Says (National Geographic News)

About other animals that resemble worms:
- A squirmy jellyfish