We’ve met this critter before. The Laotian Rock Rat (Laonastes aenigmamus) was #10 on the Top Cryptozoology Stories of 2005.
The discovery of Laonastes aenigmamus, which literally means "a stone-dwelling puzzle-mouse," occurred when an alert member of the New York-based Wildlife Conservation Society spotted the rodent on sale for cooking meat at a Laotian food market. Of course, the local people were already familiar with the animal. They call it kha-nyou.
But now, comes news from Science that the kha-nyou are not merely a new animal but one that represents an ancient family, the extinct Distomydae, a family of rodents that lived a very long time ago in south Asia and Japan.
The discovery of the kha-nyou is giving scientist permission to talk more openly about what they call the "Lazarus effect," which is defined as when an animal, long thought extinct, suddenly is rediscovered. Kha-nyou, for example, is a modern member of an ancient rodent family last seen as an 11 million-year-old fossil paleobiologists identify as Diatomys shantungensis.
The Washington Post even evoked an animal well-known to cryptozoologists in their discussion of this phenomenon: "The Lazarus effect has been observed before, most notably with the reemergence in the Indian Ocean in 1938 of the coelacanth, a Paleozoic fish believed to have gone extinct along with the dinosaurs 65 million years ago."
Carnegie Museum of Natural History paleontologist Mary Dawson, the lead author of an article in the journal Science that links the modern-day kha-nyou with the Diatomys of the past, notes the Lazarus effect is extremely rare among mammals.
"I had heard about a paper describing a new family of rodents, which is a real surprise," Dawson said in a telephone interview. "When we saw the illustrations, we knew it was a living diatomid."
University of Chicago paleobiologist David Jablonski in the 1980s invented the concept of the Lazarus effect as a cautionary tool in evaluating the fossil record.
"You may not have an extinction," Jablonski said in a telephone interview. "You’re just missing a lot of information." He noted that coelacanths have "a whopping Lazarus effect in terms of time — they’re found in deep water and don’t have an easily accessible fossil record on land."
In terms of cryptozoology, while unknown to most, there has been a debate in the field for about three decades as to whether cryptids that have gone extinct should even be considered animals of concern to cryptozoology. For example, some would say that the ivory-billed woodpecker should not be seen as of cryptozoological interest. Conservative cryptozoologists feel only brand new animals, unknown completely to science, are worthy of study.
But as has been pointed out many times, when a cryptid is as yet undiscovered and merely its traces are being found and it is being sighted in its habitat, no one knows whether it is an entirely new animal or an extinct animal that may soon be re-discovered.
The extreme example is that when Bigfoot is discovered and if it is found to have been a Paranthropus, an extinct species and genus reappearing that exists in the fossil record, that will not lessen its authentic interest to cryptozoology. It would have been a cryptid for all of those years, no matter what affinities, whether extinct, or totally new and with no known fossil precursors.
The same is true whether the cryptid is, for instance, of the recently extinct Thylacine of Tasmania or the Yeti of Nepal-Sikkim. A cryptid is an undiscovered or re-discovered species, ethnoknown to the locals first and then verified by zoologists and other scientists. The former cryptid Kha-Nyou, now "discovered," can be called the kha-nyou, and is a perfect illustration.