Subspecies differentiation in an enigmatic chaparral shrub species.

Premise: Delimiting biodiversity units is difficult in organisms in which differentiation is obscured by hybridization, plasticity, and other factors that blur phenotypic boundaries. Such work is more complicated when the focal units are subspecies, the definition of which has not been broadly explored in the era of modern genetic methods. Eastwood manzanita (Arctostaphylos glandulosa Eastw.

Lucky morning glory, Calystegia felix (Convolvulaceae): a new species from Southern California, with notes on the historical ecology of the Chino ciénega belt.

A new morning glory, Calystegia felixProvance & A.C. Sanders sp.

A Pleistocene clone of Palmer's oak persisting in Southern California.

Background: The distribution of Palmer's oak (Quercus palmeri Engelm.) includes numerous isolated populations that are presumably relicts of a formerly larger range that has contracted due to spreading aridity following the end of the Pleistocene.

Principal Findings: We investigated a recently discovered disjunct population of Palmer's oak in the Jurupa Mountains of Riverside County, California.