Lachneratus phasmaticus also known as the Phantom cardinalfish, is a species of fish in the family Apogonidae, the cardinalfishes. It is the only member of its genus. It is native to the tropical eastern Pacific and Indian Oceans. This fish can be found in crevices and underwater caves, and it occurs at depths of 3 to 104 meters. It grows to a length of 7.4 centimetres (2.9 in) SL.