Sonali and the giant rat
A giant rat that no-one has ever seen before has been discovered by explorers in the crater of an extinct volcano.
It's about the size of a cat, measuring 82cm and weighing 1.5kg, and is probably the biggest rat ever seen.
The massive rodent, called the Bosavi Woolly Rat, has got thick black fur and is not scared of humans.
It's one of a number of strange new animals found by the BBC expedition team in Papua New Guinea, which is in the Pacific Ocean.
Explorer talks to Newsround
They entered the volcano's crater to explore forests where few people have ever been before.
Overall, the team think they've discovered up to 40 new species including 16 types of frog, over 20 types of creepy crawly and a small bear-like creature called the Bosavi Silky Cuscus.
It's hoped that the new findings will help protect the part of the world where the newly discovered animals live.