Descriptions : Adult 10-12cm TL, 5-6 cm SVL. Japanese geckos are bright gray or dark gray with dark bands on their backs. Eyelids do not move. They have expanded toe pads, 2-4 cloacal spurs on each side of the tail, enlarged tubercles on the back, forearm and shank. Females store calcium on their necks. The Male has preanal pores. Japanese geckos are common reptiles in a city.
Habitat and habits : Japanese geckos mainly inhabit houses or shacks in human habitations. A juvenile was found from the 10th floor of apartment in a city area. In some islands, Japanese geckos and Tawa geckos occur hibernating at same outcrops. Japanese geckos are nocturnal and feed on insects that gathered to lights.
Breeding : , Females lay 1-2 clutches of 2 eggs in May to August. Eggs occur in a shutter case or crevice in the wall. They hatch in about 50 days. The courtship and mating are not clear. T. Kameyama and S. Okada obserbed a mating in October 1998, but unfortunately they were separated each other by a flashlight.
Range : Japanese geckos range from Japan, Korea and China. In Hiroshima, this species are found from islands and cost, also found from human habitations of the north Hiroshima such as Miyoshi-shi, Futami-gun and Yamagata-gun.
Memos : House geckos are called "Yamori" in Japan. It means a house guardian.