The species is endemic to northern South America.

The genus Erythrolamprus belongs to the subfamily Dipsadinae, which is sometimes referred to as the family Dipsadidae.

Recent phylogenetic analysis of morphological and molecular DNA evidence has shown that Erythrolamprus reginae is now likely paraphyletic.

However, based on notable differences in coloration and scale counts, it is now considered to be a separate species.

[4] The relationships of Erythrolamprus species located in northern South America can be shown in the cladogram below:[4] E. poecilogyrus (paraphyletic) E. ceii E. poecilogyrus (paraphyletic) E. miliaris E. miliaris E. typhlus (Brazil) (paraphyletic) Erythrolamprus reginae (paraphyletic) Erythrolamprus reginae (paraphyletic) E. zweifeli E. breviceps E. epinephalus (Peru) (paraphyletic) E. epinephalus (Costa Rica) (paraphyletic) E. pseudoreginae E. melanotus E. atraventer E. jaegeri E. almadensis E. juliae E. cursor E. typhlus (French Guiana) (paraphyletic) E. cobella E. aesculapii (Brazil) (paraphyletic) E. ocellatus E. aesculapii (French Guiana & Guyana) (paraphyletic) E. bizona E. mimus It feeds on frogs, frog eggs, tadpoles, fish, small birds, and lizards.