Analysis reveals that specimens of New Guinean freshwater crocodile belong to two species rather than one.

Dozens of skulls tucked away in museums have yielded a toothy surprise: a new species of crocodile that measures some 3 metres long and is very much alive.

Researchers routinely discover new species of ant and frog, but undocumented large species turn up only rarely. Christopher Murray at Southeastern Louisiana University in Hammond and his colleagues tracked down one such animal by investigating reports that individuals in the northern and southern populations of the New Guinea crocodile (Crocodylus novaeguineae) do not look the same.

The team examined skulls of 51 museum specimens and found anatomical variations that were linked to the animals’ region of origin. For example, crocs from the south of the island of New Guinea tend to have shorter snouts than do northern animals.

Skull bones of the newly named species Crocodylus halli.Credit: ASIH

The researchers concluded that the southern animals are a separate species, which they dubbed Crocodylus halli.

The researchers examined three live crocodiles at a Florida zoo and concluded that all three, although previously identified as C. novaeguinea, are in fact C. halli.