A kaylo was a fruit found on an M-class 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 to the pelvic region.
In 2371, while the away team from the USS Voyager was searching the unnamed 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")