Diogmites

The antennae have a relatively slender third article that forms over half of the antennal length and carries a single, minute apical hair.

Forelegs about two-thirds as long as hind legs, with a short but distinctive curved spine at the anterior edge of each tibia.

[1] As with most asilids, known pupae of Diogmites species have prominent tooth- or hook-like anterior protrusions of the cuticle, which are technically referred to as antennal processes.

Hanging thieves should not be confused with predatory scorpionflies of the family Bittacidae which are commonly called Hangingflies and which actually capture flying prey in a suspended posture.

[4] Chris Thawley has an interesting video of a feeding adult manipulating a large prey wasp while in hanging posture.

Robert Lavigne's Predator-Prey Database for the family Asilidae[6] has 443 records of observations for at least 20 species of Diogmites feeding on a wide range of prey, including other asilids as well as dragonflies.

Ventral view of the prothorax in Diogmites angustipennis showing the reduced prosternum typical of the subfamily Dasypogoninae
Front view of Diogmites angustipennis with claw-like spine at end of first tibia, a character typical for the genus. Another useful identifying character is the narrow face that is clearly less wide than each eye.
Hanging Thief - Diogmites properans from Okeefenokee Swamp National Wildlife Refuge, showing the tibial spine and narrow face typical for the genus
Diogmites properans (?) demonstrating the suspended feeding posture of a typical Hanging Thief
Compare and contrast: this looks like Diogmites but is actually an extra large Caenarolia species from central Argentina. Note absence of the tibial spine on forelegs and absence of pulvilli below the dagger-like tarsal claws.