Exxotaxa ▸ any taxa native in South America but without native species in Brazil, for both plants and animals; four levels.
Exxospecies ‣ ex.: Bejaranoa balansae (Hieron.) R.M. King & H. Rob.
Exxogenera ‣ ex.: Astragalus L.
Exxofamily ‣ ex.: Koeberliniaceae.
Exxorder ‣ ex.: Fagales.