Clea (gastropod)  Clea is a genus of freshwater snails with opercula, aquatic gastropod mollusks in the family Nassariidae, a family, almost all of the rest of which are marine. The members of this genus are known as assassin snails for their habit of eating other snails. They bury themselves and ambush their prey. This genus was treated within family Buccinidae. It was moved to family Nassariidae in 2016. It was classified in the newly established subfamily Anentominae within Nassariidae in 2017. Species within the genus "Clea" include:   The following species are treated within the separate genus "Anentome". Previously they were treated within the subgenus "Anentome". Synonyms:  This genus occurs in Asia and Africa. "Clea" consists of defined male and female genders and is not capable of gender change. It is unknown as to how to sex these animals. Both males and females seem to be the same size and shape. When a male and female mate, they lock together for 8–12 hours. Like all snails in the clade Neogastropoda, snails in this genus are carnivorous. They feed on different types of worms and gastropods, often eating other, larger snails after burying themselves and ambushing their prey. Some members of this genus is a part of ornamental pet trade for freshwater aquaria.