LETTERS TO THE EDITORS
To the Editors:
In “The Rarest Snail in the World” (November–December), Pat Shipman describes a very localized land snail, Cerion nanus, on Little Cayman. That species may or may not be the rarest snail in the world. Cerion diversity on low, dry islands such as the Caymans is nothing compared to that in Cuba and Jamaica, which have far more land snails than any other countries in the world.
In Jamaica, a couple of schoolteachers in the 1800s assembled enormous Cerion collections as a hobby. Many of those species were about as localized as C. nanus. Some were found only on one small part of a hill or valley, and several are represented by a single specimen. Jamaica has changed far more than Little Cayman since the 1800s, and many—if not most—of its snails are probably now rarer, or even extinct.
The Jamaican and Cuban Cerion species constitute a very rare example of explosive diversification and specialization, like the Hawaiian Drosophila species or the Lake Victoria cichlids. But, to my knowledge, no one has studied the snails since amateur collectors first tentatively named and sorted them. I looked at their collections briefly about 20 years ago, in the Institute of Jamaica in Kingston, and found thousands of shells in old, wooden drawers that had not been opened in perhaps a century. The drawers were literally crumbling from dry rot or termites. They are a scientific treasure house waiting to be opened by a serious modern taxonomist and evolutionary biologist.
Thomas J. Goreau
Global Coral Reef Alliance