For more than three decades, landscape painters Sushe and Tracy Felix have been on the leading edge of contemporary Western art. The wife-and-husband couple live together, but work separately, and each is a major star of the genre. They have placed works in top-tier regional museums, private collections and in respected galleries, such as the William Havu Gallery in the Golden Triangle, where they are exhibiting recent paintings right now. To see the art “Invisible Horizons,” with recent paintings by Sushe and Tracy Felix, continues through June 6 at William Havu Gallery, 1040 Cherokee St.