I found an very interesting post from Clanman from 2007:
"The clan of Gilleandrais -the servant of St. Andrew, ecclesiastics of Applecross founded on the west coast of Scotland in 671 by St. Mael Rubha of Bangor. The family septs of ÓBeollain [Boland], Anderson, Cairney, Fairlie, Forbes, Foulis, Gillanders, Munro, Reid, Ross, MacTaggart and Urquhart."
Gilleandrais may purportedly be an ancestor of Ferchar Mackinsagart:
EDIT to add:
Quote: „Ferchair Mac an t'Sagairt, was the grandson or great-grandson of Gillandres, one of the six Earls (mormaers) who besieged King Malcolm IV at Perth in 1160. The 'Celtic Scotland,' Vol. II, p.412, states that „the hereditary priests according to tradition, bore the names of O'Beollan and McVuirich in the Black Book of Clanranald“ – and says that Ferquhard (Mackinsagart) was descended from Gillapatrick the Red, the son of Roderick known traditionally, as the Red Priest.“
http://www.rootschat.com/forum/index.php?topic=227722.msg1206090#msg1206090