Photonic fleas were tiny flying arthropods native to the Delta Quadrant. They built flimsy webs and fed on plasma particles.

A mating pair of photonic fleas were inadvertently brought aboard the USS Voyager in 2376 within a shipment of amber spice. The insects nested near a plasma conduit, causing a momentary loss of sensor resolution whenever they tapped into the conduit for nourishment. After their discovery, Captain Kathryn Janeway decided that they should be moved to a more suitable home. (VOY: "The Voyager Conspiracy")