Any robber fly that will take on the aggressive Eastern Pondhawk dragonfly and just knock him down and eat him is a powerhouse insect anywhere. But Triorla interrupta does appear to fear no food item. "If it flies, eat it" is the Triorla rule. Or knock it down, taste it and possibly eat it. Though I have never seen a robber reject a food item after taking it down.

This is a female T. interrupta. Note the two half blocks of black then the two larger black blocks then the dark and pointed abdominal tip. This and the gray-brown color overall are enough to identify this girl in the east.

This is the male Triorla with a more reasonable moth kill. Interestingly enough, the drops of blackish oil on the stone, which I have now seen near several robber kills, are likely the injectable mix of toxins that the robber uses in its deathtool of a beak. Yikes. It gets so excited sometimes that it fires off some premature paralytic, melt-you-until-you-are-good-and-gooey toxin.

In open areas, grasshoppers are the favorite Triorla food. And, in rough roads through open grassy areas, Triorla is the dominant robber in my area. This is another male.

Another male with a Fiery Skipper kill. Fast butterflies and very difficult meals. Again impressive.

Female with hopper.

Again a dragon. This time a Wandering Glider. And what a disproportionate kill. I saw the dragon knocked out of the air. Thought it had a heart attack until I went to have a look.

If we weighed all the above prey from Triorla I am not sure this massive horse fly would not win the competition. I also believe that due to the fused eyes this is a male horse fly. Species is Tabanus atratus and it is one of the giant species in the east. I rarely see male Tabanids in the free world.