Chironius is a genus of New World colubrid snakes, commonly called sipos (from the Portuguese word cipó for liana), savanes, or sometimes vine snakes. There are 23 described species in this genus.
Nota bene: A binomial authority in parentheses indicates that the species was originally described in a genus other than Chironius.
The specific names, brazili and spixii, are in honor of Brazilian herpetologist Vital Brazil and German biologist Johann Baptist von Spix, respectively.[2]
The St. Vincent Blacksnake, Chironius vincenti is listed as critically endangered by the IUCN Red List due to its extremely limited range on the Island of St. Vincent.