Bark scorpions (Centruroides exilicauda, formerly Centruroides sculpturatus) are medium sized (about 3 inches long), yellowish scorpions with long, thin pincers and a long, thin tail. There is a darker stripe down the center of the back.

Around Las Vegas, this species is more likely to be found on block walls and inside houses than out in the desert. As such, this is the species most people are likely to see. Unfortunately, this species also has the most toxic venom for humans.

Bark scorpions are most common in southern Arizona, but they occur in the Grand Canyon, southern Nevada, and southern California. This species is not native to Las Vegas; they were imported with plants from Arizona and are quite common in some parts of town.

The diet generally consists of soft-bodied invertebrates, which are typically ambushed from a vertical surface (e.g., block wall) in a head-down position. Like all scorpions, bark scorpions give birth to live young which are carried for a time on the mother's back.