The Nandids belong to the order Perciformes, sub-order Percoidei and are grouped under the family Nandidae. The Nandids differ from their related families mainly in skeleton structure. Usually they possess big mouths, capable of opening out to a fairly, fantastic extent, nearly transparent caudal fins, and clear parts in the rear of their anal and dorsal fins.
The family is small, and related only to India, Siam, Burma and also the Malay Peninsula.