Hagenomyia tristis is an African antlion species. It is known as the gregarious antlion as it is often found in swarms in long grass in the shade of trees.[1] The range of this species extends from eastern South Africa to Cameroon and Ethiopia; it is also found in Madagascar. The larvae build sand pit traps to capture prey. This species is believed to be the mimic of Banyutus lethalis, with both species commonly swarming together.