Is that not one of the most completely boss things you've seen all week? It's by freelance artist Per Haagenson. Check out a big version of it here. It was a freelance piece done for an insecticide company called Orthene. I can only imagine it hanging behind the glowering, icy-eyed CEO of the company.
Tip of the pith helmet to Matt Tames, who happens to be on my production team at the publishing house where I work! He is, coincidentally enough, a paleoartist who has done work for the Indianapolis Children's Museum. He keyed me in on this painting, and it is also his desktop background.