Not indigenous, but apparently becoming naturalized.
Introduced to the country. Not endemic
Arrived in the geographical area specified from somewhere else by any means (adjective); not native (non-indigenous) to the area in which it has arrived. Because of its usefulness, this expression deserves far wider use in the literature than it has obtained.
a. (L. advenire, to arrive) a plant that is not native to the environment.
A species that is not native and has been introduced into the area but has not become permanently established.
not native and not fully established; locally or temporarily naturalized; "an adventive weed"
an exotic plant that is introduced and naturalized.
introduced to an area recently. cf. introduced, naturalised.