The alleged smuggling came to light when staff from a hotel where the visitors stayed in the southwestern city of Amami alerted environmental officials.
The guests “had asked the hotel to watch their suitcases, and the suitcases made a rustling noise” on Tuesday, police told The Japan Times newspaper.
Police detected thousands of the spiral-shelled hermit crabs, weighing around 160kg (353lbs) in total, inside the six suitcases they had left behind.
Liao Zhibin, Song Zhenhao and Guo Jiawei were arrested for possessing the crustaceans without proper authorisation, following their return to the hotel on Wednesday, Kyodo News reported.
The land hermit crabs were from a species designated as natural monuments because of their cultural and scientific value, and protected by Japanese law. Each one can sell for up to 20,000 yen (US$137).
