A routine shopping trip in a market in central Laos has yielded much more than a good bargain. Scientists have discovered a unique long-whiskered rodent representing a previously unknown mammal family.

The locals were already familiar with the species, which they had dubbed Kha-Nyou. But when Robert Timmins of the Wildlife Conservation Society first spied it for sale on a table at the hunters market, he immediately recognized it as exceptional. Timmins and his colleagues at the World Wildlife Fund in Thailand soon gathered other specimens from hunters and recovered bone fragments from the creature in an owl pellet. Genetic analysis and a morphological study of the animal's skull and bone structure indicate that Kha-Nyou represents a new family, genus and species--one that diverged from other rodents millions of years ago.

The creature, which scientists have renamed Laonastes aenigmamus, seems to prefer forest cover and limestone outcroppings for its living quarters and it is believed to be a nocturnal vegetarian. "To find something so distinct in this day and age is just extraordinary," Timmins remarks. "Skeptics might say that if we are still discovering such amazing new animals, why are people worried about wildlife loss. But of course it is an indication of how little we know and a window onto what we could be losing without ever knowing." The discovery is detailed in a paper published in a recent issue of the journal Systematics and Biodiversity.