Borrichia x cubana (B. frutescens x arborescens): Interspecific Hybridization in the Florida Keys

Publisher Website
Google Scholar
Abstract
B. frutescens and B. arborescens are essentially allopatric except in subtropical south Florida [USA] and Bermuda. In the region of sympatry in Florida the species form hybrids, originally described as B. cubana. Nine populations of hybrids were examined. Analysis of morphological characteristics of 64 individuals from the single population studied intensively indicated that the population was a hybrid swarm. Some individuals were also determined to be chemically intermediate between the parental forms. Both parental species and the hybrids formed 14II during meiosis. Experimentally produced hybrids were morphologically similar to the wild plants. An experimentally produced F2 backcross individual indicates the possibility of some B. frutescens traits introgressing into B. arborescens. The presence of B. frutescens in the Florida Keys may be influencing the direction of evolution of B. arborescens there.