Aritaerius pallidus

Diagnosis
Aritaerius pallidus is the only long-legged and pilose hetaeriine without any modifications of the pronotal disc. The pronotum of this species is truly subcylindrical, lacking carinate margins and lateral pronotal striae. While species of Chrysetaerius and Latronister bear a superficial resemblance to A. pallidus, the pronotal margins of these taxa are carinate. Aritaerius pallidus further differs from Chrysetaerius in having a smooth metasternal disc without any microsulpture. The eyes of A. pallidus with their large ommatidia are quite different from those of other similarly looking long-legged hetaeriine species. The aedeagal phallobase of both Latronister and Chrysetaerius is longer than the parameres whereas the opposite holds true for A. pallidus.

Distribution
Mexico; United States: Arizona

Biology
Almost nothing is known about the biology of A. pallidus except that it is attracted to ultraviolet light, indicating that this species is occasionally active at night. The large ommatidia of the eyes are characteristic of nocturnal insects. The nocturnal habits of A. pallidus suggest that its ant host might also be nocturnally active. A possible candidate is the army ant Neivamyrmex. These army ants are mainly subterranean and most above-ground activities occurs from dusk to dawn, especially under hot desert conditions (Gottwald 1995). Dispersing A. pallidus would likely have a higher rate of success encountering a new host colony at night when Neivamyrmex are foraging.