Monotypic Oleaceae genera

thumb|flowering in :ko:괴산 추점리 미선나무 자생지|Goesan Chujeom-ri Misennamu Habitat Abeliophyllum, the miseonnamu, Korean abeliophyllum, white forsythia, or Korean abelialeaf, is a monotypic genus of flowering plants in the olive family, Oleaceae. It consists of one species, Abeliophyllum distichum , endemic to Korea, where it is endangered in the wild, occurring at only seven sites. It is related to Forsythia, but differs in having white, not yellow, flowers.

Fontanesia is a genus of flowering plants in the family Oleaceae, usually treated as comprising a single species Fontanesia phillyreoides, though some authors split this into two species (see below). It is native to southern Europe (Sicily), southwestern Asia (Lebanon, Syria, Turkey) and eastern Asia (China), with two well-separated populations.

Hesperelaea is a monotypic genus of trees in the olive family which contains the single species Hesperelaea palmeri, now probably extinct. The species was found only on Guadalupe Island, a small island in the Pacific Ocean, part of the Mexican state of Baja California, about southwest of Ensenada. It was collected once in 1875 by Edward Palmer, who found three living individuals. He remains the only recorded person to have seen the species alive. The small population of the species, the devastating effects of feral goats, and the overexploitation of the island's woody plants likely meant that