The tarantula hawk wasp (Pepsis formosa) was designated the official state insect of New Mexico in 1989. Initiated by Edgewood, New Mexico elementary school students doing research on states which had already adopted insect symbols, they selected three insects as candidates and mailed ballots to all New Mexico schools for a state-wide election. As part of the project, the entire class attended the legislative hearing in Santa Fe when the bill was introduced.

These huge wasps (the largest wasps in the United States - up to two inches long) feed on nectar, but procreate in a particularly morbid fashion (the basis for their name). When a female is ready to lay her eggs, she seeks out a tarantula and injects it with paralyzing venom. She drags the tarantula to a burrow and stuffs it down the hole, then lays her eggs on top of the paralyzed spider. Several days later the eggs hatch and the larvae feed on the still living tarantula.

Several species of wasps known as "tarantula hawks" inhabit the deserts of the southwest that build nests in the ground and provide their young with spiders for food (Pepsis formosa and Pepsis thisbe are probably the two most common). The majority of these wasps have metallic blue bodies with fiery red or orange wings, and long legs ending in hooked claws.

Source:

Tarantula Hawk Wasp: Mojave National Preserve
New Mexico Symbols - State Insect: SHG Resources

Links:

State Insects - 50 States List