Scottish Conservative MSP Alex Johnstone has died aged 55.
Tributes have been paid to the North East MSP, who had served at the Scottish Parliament since 1999.
The Kincardineshire-born former dairy farmer passed away shortly after being diagnosed with cancer.
Scottish Conservative leader Ruth Davidson said Mr Johnstone was "a big man with a big heart" who "embodied politics at its best".
He was the longest-serving Scottish Conservative MSP at Holyrood, and the only one to have served continuously from the beginning of the parliament.
Hailing from Stonehaven in Aberdeenshire, Mr Johnstone worked as a farmer before being elected to Holyrood in 1999.
He served as his party's chief whip, as well as acting as spokesman for portfolios including housing, transport and rural affairs.
In the most recent session of parliament, Mr Johnstone was deputy convener of the finance committee and a member of the parliament's corporate body.
Mr Johnstone is survived by his wife Linda and their two children.
Ms Davidson said: "Alex's passing is an enormous loss for the Scottish Conservative party, for the Scottish Parliament, and for Scottish public life generally.
"He was a big man with a big heart. He embodied politics at its best: trenchant in his views, always up for a political fight, but respected and admired by all sides of the political divide for his decency and generosity.
"Alex was this huge big healthy farmer who looked like he could wrestle a cow every day until sundown, and to be hit so hard and decline so fast, at the age of 55 it's a bit of a shock.
"The north east of Scotland could not have had a greater friend over the 17 years he served as their MSP. He was utterly devoted to championing the area.
"All our thoughts and prayers are now with Linda and their family."
First Minister Nicola Sturgeon said she was "so sorry" to hear the news.
She added: "Alex never let political differences stand in the way of friendship and courtesy.
"Alex was an asset to his party and to the Scottish Parliament. He will be greatly missed and my thoughts are with his family and friends."
Scottish Labour leader Kezia Dugdale said: "Alex had a reputation around the Scottish Parliament as a great character. When our politics can feel divided, he was always quick to inject some much needed humour.
"Alex was a politician respected across the chamber, and I hope his legacy is one of goodwill in our politics."