Hadena ectypa (Morrison, 1875) (Noctuidae: Noctuinae: Hadenini) is a rarely encountered moth of conservation concern, inhabiting forest and woodland openings and edges in eastern North America. A population discovered in 2002 in Massachusetts (USA) is the first record of this species in New England. Hadena ectypa larvae from this population were reared in 2003, 2009, and 2010; the immature stages and life history are described. Parasitism by a species of Eulophus Geoffroy, 1762 (Hymenoptera: Eulophidae) and predation by Toxomerus geminatus (Say, 1823) (Diptera: Syrphidae) were observed. The native host plant of Hadena ectypa is Silene stellata (L.) W.T. Aiton (Caryophyllaceae), however, the population in Massachusetts uses introduced Silene vulgaris (Moench) Garcke as the primary larval host. Hadena ectypa could have adopted S. vulgaris as a novel host at any time during the past 200 years. S. vulgaris shares a number of traits with S. stellata that may have facilitated this host shift. Many of these traits are also shared by another introduced species, Silene latifolia Poiret, and while Hadena ectypa will feed on this plant in captivity, is not known to use it in the wild. The adoption of S. vulgaris as a larval host may allow Hadena ectypa to spread to new, weedier habitats, to increase its geographic range, and to increase its propensity for a second annual generation.