Two new species of shrewlike rats have been discovered living in the montane and mossy forests of Luzon Island, Philippines.
“These rodents are quite bizarre,” said Dr. Eric Rickart, a curator of the Natural History Museum of Utah.
“They hop around on their sturdy hind legs and large hind feet, almost like little kangaroos. They have long, delicate snouts, and almost no chewing teeth.”
“They’re very docile, very cute,” added Dr. Larry Heaney, a curator at the Field Museum.
“Their fur is short and very, very dense, like a plush toy. They make little runways through the forest and patrol these little trails, day and night, looking for earthworms.”
The new species are named the Mingan shrew-rat (Rhynchomys mingan) and the Labo shrew-rat (Rhynchomys labo).
“The species names are for the mountains the rats are found on,” the researchers explained.
“One from Mt. Labo, a dormant stratovolcano at the base of the Bicol Peninsula of south-eastern Luzon, the other from Mt. Mingan, the highest peak in the central Sierra Madre of east-central Luzon.”
The two new rodents are examples of the generally poorly-known, incredible biodiversity of the Philippines, which boasts more unique species of mammals per square mile than anywhere else on Earth.
“Mountains like those on the Philippines were the perfect breeding ground for new species of mammals,” the scientists said.
“The different habitats at different elevations on a mountain can lead to different adaptations by its mammal residents, and their diversity actually increases as you go up higher into the mountains.”
“Furthermore, the mammals on one mountain are isolated from their relatives on other mountains.”
“Generations of isolation eventually lead to new species forming on different mountains, the same way that unique species emerge on islands.”
The researchers hope that the discovery of the two new species of shrewlike rats will serve as an argument for protecting the mountainous forests where they’re found.
“Every time we find a reason to say, ‘This place is unique,’ that tells people that it’s worthy of protection,” said Dr. Phillip Alviola, from the University of the Philippines.
The discovery was announced in the Journal of Mammalogy.
Eric A. Rickart et al. Two new species of shrew-rats (Rhynchomys: Muridae: Rodentia) from Luzon Island, Philippines. Journal of Mammalogy, published online June 6, 2019; doi: 10.1093/jmammal/gyz066