Correction 10 September 2009: Since the Lost Land of the Volcano programme was broadcast on Tuesday 8 September, we've learnt that this parrot may have been mis-identified. Ornithologist Dr Jack Dumbacher now believes the parrots filmed may be yellow-capped pygmy parrots (Micropsitta keiensis), not buff-faced pygmy parrots (Micropsitta pusio). At an average height of 9 to 9.5cm, the closely-related yellow-capped pygmy parrots are slightly taller than buff-faced pygmy parrots.
The world's smallest parrot has been filmed in the wild for the first time by a BBC expedition.
The team, filming in Papua New Guinea for the programme Lost Land of the Volcano, caught two of the buff-faced pygmy parrots on camera.
On average, buff-faced pygmy parrots (Micropsitta pusio) are not much bigger than a human thumb, standing less than 9cm tall and weighing 11.5g (0.41 oz).
The Lost Land of the Volcano series will broadcast on BBC One on Tuesday 8 September at 2100 BST.