Family Atyidae is one of the oldest decapod groups, comprising prawns, mostly belonging to genus Caridina, that are considered to have completely established in freshwater. However, two of the three Caridina species available in Ratnagiri area, west coast of India viz. Caridina gracilipes and C. prox. shenoyi could not complete their metamorphosis without addition of some amount of seawater to culture media. Salinity experiments were, therefore, conducted both on adults and larvae. The results which indicate their euryhaline behaviour also reveal that adults can tolerate salinity ranges upto 28.0 and 31.0 ppt while the larvae can successfully metamorphose in ranges from 3.5 to 24.5 ppt and 3.5 to 28.0 ppt respectively. Number of larval stages is not affected by salinity.