Examine confirms extinction of three large rodents within the Philippines

Artistu2019’s conception of the three extinct cloud rats based on their living relatives. From above, Crateromys, Carpomys and Batomys.

Artistic idea of ​​the three extinct cloud rats based on their living relatives. From above, Crateromys, Carpomys and Batomys.

A new study published April 23 in the Journal of Mammalogy confirmed the recent extinction of three previously unknown species of giant rodents found only in the Philippines.

Known locally as Buot or Bugkon, the giant cloud rats live in trees and eat leaves, buds and seeds. They have furry or fluffy tails and a distinctive coat color. These giant rats and their relatives are members of an ancient branch on the Tree of Life that came from mainland Asia about 14 million years ago. All three of these newly discovered species are considered extinct by the authors.

The largest of the fossil punch rats is the Carpomys dakal, so named because it is much larger compared to the known living species of the same genus, Carpomys melanurus and Carpomys phaeurus. Dakal means large or large in several languages ​​in northern Luzon, including Itawes, Ibanag, and Agta. The second fossil species, Crateromys ballik, is slightly smaller than the living Crateromys species on Luzon, Crateromys schadenbergi. Ballik means small in the Dupaningan language Agta. The third species, Batomys cagayanensis, is named after the place where the archaeological sites are located, the Cagayan region in northeast Luzon. The scientific names of the three new species of fossil cloud rats were selected using indigenous terms from Filipino languages.

Dr. Janine Ochoa, lead author and assistant professor of anthropology at the University of the Philippines – Diliman, said the smaller mammals had been underdiscussed, likely because research focused on open-air locations where the large fossil mammal faunas were known to have been preserved, rather than the careful sifting of Cave deposits that hold a wider range of vertebrate sizes including rodent teeth and bones.

“We have had evidence of extinct large mammals on Luzon for a long time, but there is virtually no information on fossils of smaller mammals,” said Dr. Ochoa.

Extinct mammals previously known from Luzon include two species of elephant, a species of rhinoceros, a giant pig, and relatives of the living dwarf water buffalo, Tamaraw.

Marian Reyes, zoo archaeologist at the National Museum of the Philippines (NMP) and one of the authors, said some of the fossils unearthed in the 1970s and 1980s at the National Museum of the Philippines (NMP) were awaiting detailed study.