Introduced species: A species which has been introduced by man from somewhere else, generally another country. Bahiagrass, bermudagrass, Ormia depleta, Larra bicolor, and Steinernema scapterisci were introduced into the USA for very practical reasons. Large numbers of species of ornamental plants have been introduced and, unfortunately some of them have become weeds. The pet trade introduces animals from other countries, and some of these escape from their owners or even are released deliberately. Consequently, southern Florida is now home to quite a few introduced species of parrots which have established flocks in urban areas (contrast with immigrant species).