Naturalists were flabbergasted by the finding during their recent trip to Dunollie Wood on the Isle of Luing, west coast of Scotland.
The hazel glove fungus, which looks like a bulbous hand grabbing a branch, was spotted by retired Countryside Ranger Richard Wesley from Cullipool.
"After resting on a log, I looked down and to my surprise spotted a windblown twig with a small sample of hazel glove, as though it had been placed there for me to find," said Richard.
Hypocreopsis rhododendri, the hazel gloves fungus, is a priority species on the UK Biodiversity Acton Plan and Scottish Biodiversity List.
"Hazel glove is an indicator of high quality temperate rainforest so we are really pleased it has been identified at Dunollie Wood," said George Anderson, of Woodland Trust Scotland.
"It might surprise a lot of people to know Oban is a town with a rainforest at its back.
"Last year we formed the Atlantic Woodland Alliance, a partnership with other landowners, community and conservation groups which aims to secure a better future for this dwindling habitat."
He said Scotland’s rainforest is just as lush and important as tropical rainforests in other parts of the world, but its flora and fauna is even more rare.
"It is found along the west coast and on the inner isles and is a unique habitat of ancient native oak, birch, ash, pine and hazel woodlands and includes open glades and river gorges," he continued.
"Our rainforest relies on mild, wet and clean air coming in off the Atlantic, and is garlanded with a spectacular array of lichens, fungi, mosses, liverworts and ferns.
"Many are nationally and globally rare and some are found nowhere else in the world."