Hellgrammites are an insectoid species that hail from the late planet Hellgram.
An unnamed Hellgrammite was arrested by Krypton's military guild, brought before Alura Zor-El, and sentenced to Fort Rozz. After Fort Rozz's crash to Earth, the Hellgrammite escaped along with the rest of his fellow convicts. The Hellgrammite stole chemical compounds from six different chemical plants across the United States within a period of a year. He later stole from Plastino Chemicals, killing a guard who caught him in the act. At a warehouse, he was later was confronted by two Kryptonian underlings of General Astra. Though the Hellgrammite attempted to explain to the two that he didn't want any trouble and he had to eat, Commander Gor told him that if he didn't want any trouble he would have stayed hidden, and reminded the Hellgrammite that General Astra had promised to take care of all of their needs on Earth in exchange for his loyalty. He was soon confronted by Astra herself, who told him that they were stronger together and he'd help her capture her niece, Supergirl, acting as a bait. When the Hellgrammite attempted to decline as he had seen what happened to people who took on people wearing the "S", Astra made it clear that it was a command and not an invitation. The Hellgrammite later arrived at a trap set for him by the D.E.O., jumping onto the vehicle with the DDT. After being shot at by Hank Henshaw and Alex Danvers, the Hellgrammite jumped onto their vehicle, shooting stingers into several of the agents and abducting Alex, grabbing her and taking her back to Astra. He later attacked Alex who was attempting to contact the DEO through her radio, throwing her into a nearby chain-link fence. He was later defeated by Alex after she forced the stinger he had protruded from his hand into his heart. 
Hellgrammites' natural form resembles a large grasshopper-like insectoid. They possesses superhuman strength and leaping abilities, the power to secrete adhesives and weave transformative or imprisoning cocoons, and a durable exoskeleton.
Powers and abilities
- Super strength: Hellgrammites are much stronger than a normal human. One Hellgramite was shown to be strong enough to pluck Alex Danvers from a moving vehicle and carry her off.
- Super leaping: Hellgrammites are able to jump extreme distances.
- Shapeshifting: Hellgrammites are able to camouflage themselves into any shape desired.
- Stingers: Hellgrammites are able to eject lethal stingers from their body.
- Multilingual: Hellgrammites are capable of learning to speak other languages very quickly.
- Hellgrammite blood: Hellgrammites' blood had a chlorine foundation instead of being carbon based like humans. On Earth Hellgrammites must consume chemicals to replicate home planet's atmospheric conditions, DDT was the closest thing on Earth that the Hellgrammites could find to food.