Neither. It’s a really scary wasp.
A tarantula hawk (Pepsis thisbe) is neither a tarantula nor a hawk. It is a large wasp (up to 11cm, nearly 4 inches long). These can be found in the American southwest and throughout the Americas. I wouldn’t go looking for one though. They are famous for their incredibly painful sting.
The sting of a tarantula hawk ranks second highest on the Schmidt pain index.
American entomologist Justin Schmidt created the sting pain index… He once described the tarantula hawk’s sting as ‘instantaneous, electrifying and totally debilitating’.
The tarantula hawk has been awarded second place on the Schmidt sting pain index, beaten only by the South American bullet ant (Paraponera clavata).
The advice for those who are stung is to “lie down and scream“. Fortunately, for the human victims of a sting, the pain lasts only a few minutes. But they might be the longest few minutes of your life.
So, why is it called a tarantula hawk?
The “tarantula” part of the name refers not to what they are, but what they prey on. While adult tarantula hawks feed on nectar, they will sting tarantulas to serve as a parasitic host for their offspring to feed on.
An adult female will paralyze a tarantula with its stinger, and then transport the spider back to the hawk’s nest. Once there, the female lays an egg in the spider’s abdomen, then covers the entrance of the burrow to trap the spider.
Have a look at this short video from Animal Planet to see the tarantula hawk in all its terrifying glory.