David Attenborough show features first filmed sighting of Conolophus Marthae iguana - the Penny Black of the natural world

When our greatest naturalist squared up to a new species

For nearly six million years, the Conolophus Marthae iguana went about its business on the Galapagos Islands unnoticed by the wider world. Its quiet existence also meant it had evaded the attentions of humans carrying television cameras. Then Sir David Attenborough showed up.

The veteran naturalist, whose film crews would be forgiven for believing that they had captured most living creatures during his 60-year career, has become the first to take professional footage of the rare pink reptile, which lives on a single volcano in the isolated archipelago famously studied by Charles Darwin.

The broadcaster likened filming the lizard – which was only officially recognised as a separate species in 1990 after being discovered by an Italian scientist, Gabriele Gentile – to a philatelist finding a Penny Black, the sought-after stamp.

Sir David, 86, said: “It’s a remarkable thing in this day and age when you think about the number of scientists per square metre in the Galapagos, and yet suddenly we have discovered a new species.

“A little periwinkle or something which nobody has identified before, is one thing, but this is more than that, it’s a large pink iguana. I used to collect stamps, and this was a Penny Black of the natural world in a very big way.”

The iguana evaded detection by Darwin and the scores of other naturalists who have scoured the Galapagos in search of new species among its unique flora and fauna.

The lizard lives in burrows on the crater rim of the Wolf Volcano on Isabela, one of the 13 main islands. The reason for its distinctive colouring is not known, but it is thought to be distantly related to the more common yellow land iguana. The two species diverged about 5.7 million years ago and Marthae is now one of the world’s rarest creatures with a remaining population of as little as 100 individuals.

“It was a privilege to see it,” added Sir David, who first visited the Galapagos in 1978 while working on his groundbreaking BBC Life On Earth series.

The team also became the last to film the final survivor of a species of giant tortoise from the island of Pinta. The creature, known as Lonesome George, died just 10 days after filming and the species is now believed extinct. Scientists estimate he was about 100 years old.

Sir David said: “I can’t say I was surprised but I was saddened when the news came two weeks after we’d filmed.”