A kaylo was a fruit found on an unnamed planet located in the Delta Quadrant that resembled an Earth apple. Kaylos were poisonous and caused death after even one bite. The consumer's windpipe swelled and pain was felt in the lower regions of the body, starting in the knees and working its way up.
In 2371, while the away team from the USS Voyager was searching the planet for food, Lieutenant Joseph Carey found a kaylo. Carey was initially excited at the find until Neelix informed him of the deadly and painful effects. (VOY: "State of Flux")