My original tumblr post was here. This image was researched by Bacchus at ErosBlog as part of the “Δ commission.” The research was originally published at Hedonix as “Δ 071 – Cave Girl, Serpent Undies.” Here is what Bacchus found.

According to this web page, the artwork above is by Robert Gibson Jones and it appeared on the cover of the September 1945 issue of Amazing Stories:

The artist’s signature is partly visible lower right in the image. Robert Gibson Jones was a prolific pulp artist of the 1940s and 1950s. A bibliography of his many science fiction magazine covers and interior illustrations is here.