Coelostoma (Holocoelostoma) stultum, is a species of water scavenger beetle widely distributed in Palearctic and Oriental realms from West Pacific towards Indian Ocean, such as China, Taiwan, Andaman Islands, Myanmar, India, Indonesia, Japan, Korea, Malaysia, Mascarene Islands, Nicobar Islands, Oman, Philippines, Saudi Arabia, South Korea, Sri Lanka, Thailand, United Arab Emirates, and Vietnam.
Median lobe of the aedeagus of male is almost parallel with broadly rounded apex.
[5][6] The species has found commonly near the shore of paddy fields, ponds and rivers in Japan.
It produces silk from the genitalia and then spins the lower part of the egg cocoon from it.
During night time, the marsh slug, Deroceras laeve is known to prey on these eggs cocoons.