A previously unknown species of mouse has been discovered on the island of Cyprus. This is the first new terrestrial mammal species discovered in Europe in decades. "The "living fossil" mouse has a bigger head, ears, eyes and teeth than other European mice and is found only on Cyprus," Thomas Cucchi, a research fellow at Durham University in northeast England, said.

"Genetic tests confirmed that the new mouse was a new species and it was named Mus cypriacus, or the Cypriot mouse," he said. (the common house mouse is Mus musculus).

"Based on our DNA analysis we believe it has been around for perhaps half a million years," said Eleftherios Hadjisterkotis, a wildlife biologist at the Cypriot Ministry of Interior.

"The discovery is a first for Cyprus. As far as mammals in the rest of Europe are concerned, just about everything else had been discovered," said Hadjisterkotis.

The biodiversity of Europe has been extensively studied since the XIXth century; since new European mammal species are rarely found, nobody had expected the finding of new creatures as large as mice to be discovered in this area. "New mammal species are mainly discovered in hot spots of biodiversity like Southeast Asia, and it was generally believed that every species of mammal in Europe had been identified," Cucchi said. "This is why the discovery of a new species of mouse on Cyprus was so unexpected and exciting."

A bat discovered in 2001 in Hungary and Greece was the last new mammal found in Europe. "No new terrestrial mammal has been found in Europe for decades," he said.

"It is an endemic species of mouse that has somehow survived the arrival of humans and the other species of mice that people accidentally brought with them when they colonized the island," says Keith Dobney, who heads the research team at the University of Durham.

"The ancient mouse species is fairly similar to the common house mouse and so it has been overlooked until now - people must have assumed it was just a sub-species of house mouse that evolved recently on the islands," he said.

Cucchi compared fossil mice teeth from the Neolithic period with those of four known modern-day European mice species, to see if the house mouse reached the island via human colonization 10,000 years ago. One of the living specimens, thought to be morphs of the house mouse, was morphologically very similar to the fossils. The genetic tests showed that the specimens were the same species as the fossils.

The Cypriot mouse entered the island before it broke away from mainland Asia Minor. It survived man's arrival on the island and introduction of the common house mice by the humans during the same event. This species is an "ancient relic", closer to its prehistoric ancestor than any modern cousin. "The new mouse is the only endemic rodent still alive and as such can be considered a living fossil," Cucchi said.
"All other endemic mammals of Mediterranean islands died out following the arrival of man, with the exception of two species of shrew. The new mouse of Cyprus is the only endemic rodent still alive, and as such can be considered as a living fossil,'' Cucchi said.

"The discovery of this new species and the riddle behind its survival offers a new area of study for scientists studying the evolutionary process of mammals and the ecological consequences of human activities on island biodiversity,'' he continued.

Researchers from Conservation International found a new species of tree rat in the Amapa region of the Brazilian rainforest in September this year.

Photo credit: Durham University/AP