Hellgrammite was a brilliant entomologist named Roderick Rose, that subjected himself to a mutagenic process that transforms him into a grasshopper-like humanoid insect. The transformation gave him superhuman strength and leaping abilities, the power to secrete adhesives and weave transformative or imprisoning cocoons, and a durable exoskeleton. A number of his schemes revolve around transforming others into weaker, subordinate versions of himself, leading to clashes with Batman and the Creeper, and also with Green Arrow and Black Canary.
In the Post-Crisis DC Universe, the Hellgrammite returns as a recurring foe for Superman, first encountering the Man of Steel after being hired (by then LexCorp board member George Markham) to kill Lex Luthor. During the Underworld Unleashed crossover, he makes a deal with Neron, trading his soul in return for increased physical powers and an improved ability to transform others into his larvae. In a crossover special, Underworld Unleashed: Patterns of Fear, it was stated that he had once used the alias Robert Dobson. The special also confirms that his Pre-Crisis history is still largely intact.
Hellgrammite has been seen alive One Year Later, after the events of Infinite Crisis, still a member of Superman's rogues' gallery, acting as an assassin for Intergang.
In Other Media
Batman: The Brave and The Bold
He appears in the " Time Out For Vengeance" where Batman and The Creeper defeat him in the teaser.
In this adaptation, Hellgrammite is one of a race of Hellgramites. This Hellgramite was a criminal who was imprisoned in the Kryptonian prison, Fort Rozz. He has superhuman agility and can shoot spikes from his body.