Knowledge of genetic diversity informs conservation of a rare, clonal wetland plant Lilaeopsis schaffneriana subsp. recurva (Apiaceae)

Abstract

Ciénegas and other marshland habitats distributed throughout mid-elevations in the American Southwest have declined dramatically over the past century. This decline has likely affected natural processes for many plants and animals dependent on these unique habitats. The primary goal of this study is to describe genetic diversity within and among populations of the U.S. federally endangered Huachuca water umbel, Lilaeopsis schaffneriana subsp. recurva, an herbaceous aquatic perennial endemic to ciénegas and river edges of southeastern Arizona and northern Sonora, Mexico, to learn about its basic biology and inform conservation management. Population samples were collected from 13 sites across the range (287 total samples), and genetic diversity data were gathered for 13 microsatellite loci (five of which were discovered to be monomorphic). Results of data analyses of eight variable microsatellite loci revealed that most populations are dominated by a single multilocus genetic clone; only two populations have more than one multilocus genetic clone present (represented by more than one individual). Genetic diversity is low within populations, but genetic differences do exist among most populations. Those populations that are very similar to one another likely experienced recent or historical gene flow. Conservation considerations should include preserving multiple, genetically distinct populations as well as maintaining local population connectivity and quality of suitable habitat for the establishment of new clones.