Snubfins have rounder foreheads and smaller fins
A team of scientists has identified a new dolphin species - the first for at least 30 years - off north Australia.
The mammals - named snubfin dolphins - were initially thought to be members of the Irrawaddy species, also found in Australian waters.
But one researcher found the snubfins were coloured differently and had different skull, fin and flipper measurements to the Irrawaddys.
DNA tests confirmed that they were two distinct species.
The researcher, Isabel Beasley of James Cook University in Townsville, Queensland, said that because they live in shallow waters, both types face the same threats to their survival, including being accidentally caught in fishing nets.
Ms Beasley said it was impossible to know how many of the snubfins there are, though a group of 200 is thought to live off Townsville, in Australia's north-east.
Some are thought to live off Papua New Guinea as well, but the majority of the population is thought to be Australian.
"It means that Australia now has an endemic species living in its waters and it's a higher conservation priority now," she told Reuters news agency.
The Irawaddy dolphin is itself extremely rare - conservation group the WWF says fewer than 1,000 remain.
Many live in the shallow coastal waters of South East Asia, where it is considered a culinary delicacy. Commercial trade was banned last year.
Ms Beasley and fellow researchers found that the snubfin dolphin had three colours while the Irrawaddy was slate grey with a white belly.
They also concluded that the snubfin had smaller fins than most dolphins and a rounder forehead.