title: Two new Marquesan species of the southeastern Polynesian genus Oparanthus (Asteraceae, Coreopsidinae).
abstract: Two new species of the recently revised genus Oparanthus (Asteraceae, Subtribe Coreopsidinae) were discovered during the National Tropical Botanical Garden/Smithsonian Institution 1997 expedition to the Marquesas Islands. Oparanthus woodii W. L. Wagner & Lorence, sp. nov. is known from a single population on the island of Nuku Hiva, and Oparanthus tiva W. L. Wagner & Lorence, sp. nov. is known only from Tahuata. Small domatia with a tuft of hairs occur in Oparanthus tiva (and the previously known Oparanthus hivoanus), and similar but naked domatia are found occasionally in Oparanthus woodii. Domatia are of exceedingly rare occurrence in Asteraceae. Both new species are extremely rare and are considered critically endangered (CR) as are the other four species of the genus.
authors.affiliation: Department of Botany, MRC-166, National Museum of Natural History, Smithsonian Institution, P.O. Box 37012, Washington, DC 20013-7012.
authors.forename: Warren L
authors.initials: WL
authors.lastname: Wagner
authors.forename: David H
authors.initials: DH
authors.lastname: Lorence