Pepsis grossa or Tarantula Hawk wasp

Pepsis grossa formerly formosa or Tarantula Hawk Wasp
The female wasp usually attacks the tarantula in or near its ground burrow with a sting to its abdomen. When paralyzed, the wasp drags it back into the spider’s burrow and lays one egg on the spider, plugging the burrow opening. The Tarantula Wasp larvae feeds on the paralyzed living spider. Adult wasps feed on nectar and pollen.

Along with its aposematic coloration (red wings) and their dangerous stinger, considered to be the second most painful insect sting in the world, after that of the bullet ant, they have few predators. The roadrunner bird and the bullfrog are two of its few predators.

15 species of Pepsis wasps are found in the United States with 9 of those occurring in desert regions. In the deserts of Southwestern USA like Arizona where I live, two species of Tarantula Hawks are common, pepsis formosa and pepsis thisbe. These wasps can reach almost 2 inches in length. They are solitary wasps and not generally considered aggressive, but I have crossed their paths on hiking trips several times.