Clithon spinosum is a species of brackish water and freshwater snail with an operculum, a nerite. It is an aquatic gastropod mollusk in the family Neritidae, the nerites.
Distribution of Clithon spinosum includes the Indo-Pacific and it ranges from New Guinea and south-eastern Asia and eastern Asia to Marquesas. It also occurs in Japan, New Georgia,[1] Fiji and Tahiti and in French Polynesia including the following Society Islands: Tahiti, Mo'orea, Raiatea, Huahine.[2]
There are always spines on its shell.[3] Spines are long and thin and they are directed rearward. The width of the shell is 15–20 mm.[4]
Clithon spinosum is a dioecious (it has two separate sexes) and amphidromous snail.[2] Adults live in freshwater and larvae are marine.[2] Larvae are long-lived planktotrophs.[2] Adults prefer boulders and cobbles over granules as a substrate.[5] They were found mainly on bottom of rocks in aquaria and in situ. They are reported from altitude 0–10 m a.s.l.[6] They can reach densities up to 57.0 ± 17.3 snails per square meter of a stream.[6] Adults can survive 8 hours in seawater (longer exposure was not tested).[6]
It is not used as food source by humans.[2]