Alfalfa-colonization
Guides
Plebejus icarioides
Melissa blue, Fender's blue
Plebejus icarioides is a species of lycaenid butterfly commonly known as the Melissa blue. The species has been observed colonizing alfalfa in the Great Basin region, representing a notable host range expansion. One subspecies, P. icarioides fenderi (Fender's blue), is federally endangered in the United States and has been the focus of intensive conservation research. The species exhibits ant tending behavior, with caterpillars producing sugar secretions that ants collect in exchange for protection from natural enemies.