Periplaneta japonica, otherwise known as the Japanese cockroach or Yomata cockroach, was recently found in the United States for the first time. Exterminators working on the High Line in New York City found the unusual insect around stones and planting material. Many of the ornamental plants installed on the High Line were imported from Asia and it likely that the some of these plants were infested with eggs or nymphs of the Japanese cockroach.
The Japanese cockroach, unlike the American cockroach, Periplaneta americana, is adapted to cooler northern climates. It has a flexible univoltine or semivoltine (one or two year) life cycle, depending on the timing of its hatching, and is unusual in being able to spend two winters as diapause nymphs before reaching maturity.
Nymphs have been observed in the wild hibernating in sub-freezing temperatures during winter months in snow-covered habitats. Overwintering nymphs were able to survive laboratory supercooling experiments in the -5 °C to -8 °C temperature range, enduring twelve hours of tissue freezing, as well as recover from burial in ice.
The Japanese cockroach is primarily an outdoors species, though some populations are adaptable to living indoors in houses and buildings where food is stored, prepared, or served. This is in contrast to the American cockroach that is not adapted to living outdoors in the winter and will immediately move indoors when the cold weather begins.