PHYLOGENY OF RUBUS SUBGENUS IDAEOBATUS (ROSACEAE) AND ITS IMPLICATIONS TOWARD COLONIZATION OF THE HAWAIIAN-ISLANDS

Two species of Rubus occur naturally in the Hawaiian Islands, R. hawai ensis and R. macraei. it has been previously thought that R. spectabil is, a Western North American species, and R. hawaiensis share a recent common ancestor based on morphological similarity and that X. macraei was a later derivative of R. hawaiensis. DNA sequences of the chlorop last gene ndhF were used to reconstruct the phylogeny of these species with non-Hawaiian members of subgenus Idaeobatus. These findings stro ngly contradict the previous hypothesis for the origin of the Hawaiian Rubus. Although R. hawaiensis is closely related to X. spectabilis, X . macraei is distantly related to these species. Sequence identify gen etic distance, and phylogenetic analysis all suggest that X. macraei i s distantly related to New World and Asian species of subg. Idaeobatus . Consequently, X. macraei and X. hawaiensis may have arisen from two separate colonizations iri the Hawaiian Islands rather than one as pre viously assumed. The ancestry of R. macraei may trace to other Pacific Rim islands.