Hesperelaea

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 the species was extinct by the end of the 19th century. An intensive search for the plant in 2000 was unsuccessful.

Hespereleae palmeri was a compact tree or shrub high, with entire, coriaceous (leathery) leaves that were mostly oppositely arranged. The inflorescence was a terminal panicle of perfect (bisexual) 4-parted flowers. The flowers were pale or lemon yellow, the petals over long. Asa Gray considered the species remarkable for the Oleaceae in having wholly distinct petals and uniformly isomerous stamens. The fruit was drupaceous.