Hemirhagerrhis viperina, commonly known as the viperine rock snake or western bark snake, is a species of snake in the family Psammophiidae. It is indigenous to areas within southwestern Angola and northwestern Namibia.Baptista NL, António T, Branch WR. 2019. The herpetofauna of Bicuar National Park and surroundings, southwestern Angola: a preliminary checklist. Amphibian & Reptile Conservation 13(2) [Special Section]: 96–130 It is partially arboreal. The nostrils of H. viperina has a vertical piercing in their nasal.Broadley, D. G. (1997). A Review of Hernirhagerrhis Vipen'na (Bocage) (Serpentes: Colubridae), a Rupicolous Psarnmophine Snake, 1997(2), 161–169Harrington, Sean M; Jordyn M de Haan, Lindsey Shapiro, Sara Ruane 2018. Habits and characteristics of arboreal snakes worldwide: arboreality constrains body size but does not affect lineage diversification. Biological Journal of the Linnean Society 125 (1): 61–71f>
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