The Comma butterfly, which became extinct in Scotland in the 1870's, is spreading quickly through the southern half of the country, due to climate change.
The butterfly is moving north at between 12 and 15km a year, and in the last ten years has successfully colonised the Borders, all of the Lothians, Fife and the southern parts of Tayside, with recent sightings reported from Dundee and Pitlochry.
Butterfly Conservation Scotland is appealing to members of the public to help them find out how far the Comma has spread into Scotland this year.
If you spot a Comma in Scotland, please log on and submit your sighting here.
Ragged wing edges distinguish this pretty orange and brown butterfly. This, together with the distinctive white comma-shaped marking on the undersides, mean it is an easy butterfly to identify.
The Comma can be seen in gardens and woodlands from May through to September, as it has two generations a year.
They pass the winter as hibernating adult butterflies. It was feared that last year's exceptionally cold winter might have reduced Comma numbers, but recent sightings have shown that it is well established and thriving.
Paul Kirkland, Director of Butterfly Conservation Scotland said: "We need help to track this butterfly's re-colonisation of Scotland.
"The first butterflies seen a few years back were probably migrants from Northern England, but last year we were able to confirm that the Comma is once again breeding throughout southern Scotland. If the current rate of spread continues, it should arrive in Inverness by 2017!"