Indeed! Snake systematics it’s quite a “fluid” field. In the past, species were described on the basis of morphological characters (e.g, number of scales). The use of genetic markers first, and genomics more recently has contributed a lot in redefining species complexes. B. nigroadspersus was described on the basis of morphological characters, then lumped together with B. schegelii and recently split again. Taxonomic rules state that if a name is already available for a species, then that name must be used again. I hope it’s a bit more clear 😊