[2] M. tohono was originally believed to be a local varietal of Mastigoproctus giganteus, but research found that certain biological characteristics (including differing areas of setae frequency and epistoma positioning) warranted a reclassification of certain local varietals of M. giganteus into newly classified species.

[3] Etymologically, the binomial name of Mastigoproctus tohono is derived from Greek and O'odham origins.

However, its vision is extremely poor, and it primarily relies on its elongated front legs, tail, and pedipalps to navigate and sense its environment.

[4] As a defense mechanism, Mastigoproctus tohono can spray a substance composed of acetic acid from the base of its tail, which can injure the exoskeleton of invertebrates and irritate the eyes and nose of vertebrate predators.

[5] This chemical produces a strong vinegar-like odor, earning this species the common name "vinegaroon".