Inbreeding, low genetic diversity, and spatial genetic structure in the endemic Hawaiian lobeliads Clermontiafauriei and Cyaneapilosa ssp. longipedunculata

The endemic lobeliad genera Cyanea and Clermontia (Campanulaceae) are among the largest in the native Hawaiian flora, and contain large numbers of endangered and threatened taxa. As a baseline for future studies of rare species in this group, we used RAD markers to estimate genetic variation and spatial genetic structure in single populations of two common species, Cyanea pilosa ssp. longipedunculata on Hawai`i and Clermontia fauriei on Kaua`i. We found low to moderate levels of genetic diversity (H e ≈ 0.13 and π all ≈ 0.0013 for both species), consistent with studies of several other island plant species, and substantial inbreeding (F is ≈ 0.17). There was no evidence for spatial genetic structure in Cyanea , and in Clermontia SGS was weak and restricted to small spatial scales (