The bryocorine mirid Tenthecoris tillandsiae Henry (Hemiptera: Miridae) was described as a new species in 2016. Although the type locality is Charleston, South Carolina, the species is considered adventive in the United States and native to Latin America. Spanish moss (Tillandsia usneoides [L.] L.; Bromeliaceae) is the plant bug's only known host. Tenthecoris tillandsiae was found in three counties of the greater Charleston area in clumps of Spanish moss that grew on ten species of woody plants, especially Darlington oak (Quercus hemisphaericaW. Bartram exWilld.; Fagaceae) and live oak (Q. virginiana Mill.). Nymphs and adults fed on strands of the moss, on which they left dark spots of excrement. Overwintered eggs hatched in mid- to late April, with first-generation adults appearing by early May. Two additional generations were produced; nymphs were present into October, and an adult female was found as late as mid-December. Tenthecoris tillandsiae sometimes was syntopic with a native plant bug (Phytocoris tillandsiae Johnston) that specializes on Spanish moss. Pathways of entry that might have allowed T. tillandsiae to enter the southeastern United States from South America (where Spanish moss originated), Central America, or Mexico are discussed. This immigrant mirid is suggested to be a benign addition to the arthropod community associated with Spanish moss, a plant not only symbolic of the South, but also one known to help conserve insect biodiversity.