Meeting Abstract
Amynthas agrestis Goto & Hatai 1899, an earthworm native to Japan and South Korea, was first documented in the United States in 1953 and has since been reported in over 20 states with noticeable negative impacts in hardwood forests. Known colloquially as Crazy Worms, Alabama Jumpers, or Snake Worms, individuals of A. agrestis reach up to 18 cm in length and exhibit a surprisingly lively behavior when disturbed from their epigeic habitat. We are undertaking a phylogeographic analysis of A. agrestis using sequences from the mitochondrial genes cytochrome-c oxidase subunit I (COI) and 16S rRNA. Our goal is to understand whether A. agrestis is becoming established in new areas through multiple, ongoing introductions or by dispersal along a leading front from an original southern introduction. Our analyses of populations of A. agrestis from sites in northern states show the presence of shared haplotypes across sites and similar levels of genetic variation within and among populations, suggesting multiple colonization events; there is no isolation-by-distance pattern for populations of this parthenogenetic worm. Frequent human-mediated jump dispersal of the worm, probably by transport within horticultural materials or as bait, may explain our results. We will discuss these results and our analyses of expanded sampling across the range of A. agrestis. Ultimately, we hope to understand whether ongoing transport occurs directly from the native habitats of A. agrestis, or from sites within North America, so that the spread of this invasive species might be minimized or controlled.
