Hysterochelifer geronimoensis is a small, predatory insect belonging to the order Pseudoscorpiones. It is found in the arid regions of the southwestern United States, particularly in the Geronimo Wilderness area. This species has a distinctive appearance, with a dark brown body and elongated pincers used for capturing prey. H. geronimoensis plays an important role in controlling populations of other small arthropods in its ecosystem.