Balete’s mouse: new genus discovered in Davao Oriental forest

DAVAO CITY (MindaNews / 21 Aug) – A new genus of long-nosed mouse similar to a shrew has been discovered in the forests of Mount Kampalili in the province of Davao Oriental, the Chicago-based Field Museum said.

In a press release published on its website, Larry Heaney, curator of mammals at Field Museum and senior author of the paper in the Journal of Mammalogy, said the new mouse, Baletemys kampalili or Balete’s mouse, was discovered by Filipino biologist Danilo Balete. He said Balete went on expeditions to Mount Kampalili in Mindanao in 2007 and 2010 as part of a Field Museum collaboration with the Philippine Eagle Foundation, to determine what mammals lived alongside one of the largest and most critically endangered birds, the Philippine Eagle. 

^{An illustration of Balete’s mouse. Credit: (c) Velizar Simeonovski, Field Museum}

He said Balete and his team “made a startling discovery: a dark brown mouse with small eyes and a long, tapering nose like a shrew, different from anything he’d ever seen on that island. It looked more like mice he’d seen hundreds of miles away on the island of Luzon.”

“High up in the mountains, Danny was able to get cell phone service, so he sent me a text message right away, saying, ‘We just caught this animal that looks a lot like the ones from Luzon, and it shouldn’t be here,’” recalls Heaney. “So he immediately recognized that this was something really cool.”

The Filipino scientist sent three specimens of the new mouse to the Field Museum, and DNA analysis confirmed that the “rodent was different from any species known to science.”

The museum described the mountains of the Philippines as one of the most biodiverse places on the planet.

The report said its high mountains are “cooler and much wetter than surrounding lowlands and it’s difficult for small mammals to get from one mountain peak to the next. As a result, they tend to stay isolated on their own “sky islands,” evolving separately from each other and forming new species. “The taller and the bigger the mountain range, the more species of mammals will be living there that don’t live anywhere else in the world,” says Heaney.

The name, Baletemys kampalili, is derived from a combination of the Greek word “mys” which means mouse and “Balete,” in honor of its Filipino discoverer Balete, recognized for his astounding contribution to Philippine mammal’s taxonomy and conservation, while “Kampalili” is the name of the mountain where it was discovered.

The museum said that “since a genus is a higher-level group than a species, describing a whole new genus, like this mouse, is a bigger deal than finding a new species.”

In a statement on Saturday, the Department of Environment and Natural Resources (DENR)-Davao,  described the new genus as “distinct through its dark brown hair with soft, dense fur, small eyes and ears and a long, tapering nose like a shrew.”

Dakota Rowsey, a vertebrate collections manager at Arizona State University and research associate at the Field Museum, said “DNA study demonstrated that the new mouse was not related to the species up in the northern Philippines, but instead was related to species from Mindanao.”

“It appears to be a remarkable case of what biologists call convergence — distantly related species that have independently evolved to resemble each other in ways that allow them to use habitats and resources in similar ways,” he said.

Heaney added that between 50 and 100 new species of mammals have been discovered globally per year.

“Finding a brand-new genus, previously unknown to science genus like this one, that only happens at most a couple of times per year. In our 40 years of intensive study of Philippine mammals, this is one of nearly 50 new species, but just the fourth new genus we discovered,” he added. (Antonio L. Colina IV / MindaNews)