Antlions are not ants, and defintely not lions! They belong to the Family Myrmeleontidae. The larvae of the Genus Myrmeleon, build these pitfall traps in sandy sites. The larvae lie in wait at the very bottom of this cone-shaped trap, waiting for unsuspecting insects to fall in, at which, they pounce, like a lion. The larvae are quite fierce looking, judging by photos, but I've never seen one, only their distinctive traps. The adults are rarely seen, mostly because they are content to rest along branches in daytime, rendering them almost totally inconspicuous. Superficially, they look a bit like the insect in the next photo, the fishfly.