외래종이 · 외래종을
non-native species, invasive species
Example
황소개구리 같은 외래종이 토종 생물을 위협하고 있습니다.
Non-native species like the bullfrog are threatening native wildlife.
Word parts
외 outside+래 come+종 kind
Literally 'species that came from outside'; -종 = 'kind, species'.