Sillem's mountain finch Leucosticte sillemi was known only from two specimens collected by J.A Sillem on 7th September 1929 during the Netherlands Karakorum Expedition of 1929-1930 at Kushku Maidan on the West Tibetan Plateau at 5,125m. The bird has not been recorded since these specimens were collected, however, in early June 2012 Yann Muzika was trekking in Yenigou Valley of the Qinghai province in China when, confined to camp due to illness, he came across a flock of Tibetan rosefinch. In this flock was a bird which he did not recognise but which resembled Brandt's mountain finch so, fortuitously, he took a series of photographs. On returning home he submitted these to Krys Kazmierczak who manages the Oriental Bird Club photo database (http://orientalbirdimages.org) where they were correctly identified as the missing species.
There are seven species of Leucosticte distributed over Tibet, China, north-east Asia and with two species in North America. Based on current taxonomical knowledge, they are closely related to linnet, crimson-winged finch and trumpeter finch of the Western Palearctic.
Read the full story by Yann Muzika here:
http://thewildernessalternative.com/2012/10/20/sillems-mountain-finch-rediscovered/
Also:
http://orientalbirdimages.org/leucosticte-sillemi.html
http://www.bbc.co.uk/news/science-environment-20008988