Donald G. 2002.
A review of the species of Psammophis Boie found south of Latitude 12° S (Serpentes: Psammophiinae). African Journal of Herpetology, 2002 51(2): 83-119.
The status, relationships and zoogeography of the 14 taxa of Psammophis found south of Latitude 12° S are reviewed and the following taxonomic changes are proposed:
Psammophis trinasalis and P. namibensis, previously treated as subspecies of P. leightoni, are recognised as good evolutionary species which show ecological differences.
Psammophis orientalis, previously regarded as a subspecies of P. subtaeniatus, differs from the latter in a suite of characters and is parapatric with it in Zimbabwe, so it is now recognised as an evolutionary species.
Psammophis brevirostris and P. leopardinus, previously regarded as subspecies of P. sibilans (Linnaeus), are recognised as relict evolutionary species. The Zambian populations previously assigned to P. leopardinus have been described as a new species (Hughes & Wade, in press).