sky island n. an isolated ecosystem occurring at a high altitude, such as on a mountain top, which shows evolutionary tendencies similar to those occurring on islands surrounded by water. (source: Double-Tongued Dictionary)
Further reading
In 1916, a small-town newspaper in Pennsylvania printed a fanciful item about a local gathering with a guest list that included, among others, Miss Ella Vader, Mr. Ray Zor, and other punny names. This is part of a complete episode. Transcript of...
As we’ve noted, in California’s Orange County, to birdie means “to drink from a bottle without touching it with one’s lips.” Elsewhere this germ-avoidant act is also called airsipping, airing, baby birding. In parts of the UK, you might sky a drink...