Brine chemistry matters: Isolation by environment and by distance explain population genetic structure of <i>Artemia franciscana</i> in saline lakes

The American brine shrimp Artemia franciscana is important in aquaculture and has become invasive other continents, aided by dispersal via waterbirds. However, little known about processes underlying its genetic diversity population structure natural habitat North America. These processes, including local adaptation, are pivotal drivers of species distribution community structure, therefore central to aquatic biodiversity. We studied 15 populations saline lakes Saskatchewan, Canada determine the influence variation geological history, water chemistry, lake size, location. aimed relative importance isolation distance environment using cytochrome c oxidase subunit 1 gene (CO1) as a mitochondrial marker five nuclear microsatellite markers. Geographic patterns for CO1 microsatellites differed, with clustering different groups based on distances according used. better indicated historical colonisation suggesting potential routes initial when were formed after deglaciation 11,000–15,000 years ago. Differentiation between markers was strongly related hydrochemistry, suggested distance-based redundancy analysis, but there no indication distance. ratio alkalinity sum Ca Mg concentrations particularly important, although high Cl concentration caused potash mining also had unique population. Geochemistry adaptive radiation anostracan crustaceans. Our study suggests that it underlies intraspecific populations, promoting environment, making ineffective cysts moved birds hydrochemistry. ?