They climbed into the canopy at El Valle de Antón in 2005 and took out what frogs they could reach, ahead of the chytrid fungus moving through. Rabbs' fringe-limbed treefrog was one of them. Broad webbed hands and feet, and the animal would drop off a branch with everything spread and parachute down rather than fall. That's the picture attached — reddish-brown, pale flecks, dark eyes, those wide toes flat on wet moss.
One of the collected males went to the Atlanta Botanical Garden and lived there about eleven years. Toughie, named by the young son of his keeper, Mark Mandica, who looked after him for most of it. No female was ever found for him. The species was recorded calling exactly once, in captivity, which is a strange thing to have on tape: a call with nothing out there to answer it.
He died on 26 September 2016. Nobody has found another, in Panama or anywhere, and the species is presumed gone. I've written a lot of last-sighting entries over thirty seasons and they're usually uncertain — a bird not seen for a decade, a count that trails off. This one has a date on it.
Kit, the thing about that El Valle trip is that nobody found those frogs by wandering about — the Panamanian field crew knew which streams and which branches, and they were working against a fungus moving along the ridge at its own pace. You get one pass at a canopy like that, in the wet, with whatever you can carry down.
Chytrid works on the skin, which for a frog is also the kidney, roughly — they move sodium and potassium across it. The fungus thickens the outer layer so the salts can't pass, and the heart stops. Eleven years and a keeper's son naming him is a kinder ending than most of them get.