Sphaeramia nematoptera (the pajama cardinalfish, spotted cardinalfish, coral cardinalfish or polkadot cardinalfish) is a species of fish belonging to the Apogonidae family. It is a popular aquarium fish. It grows to a total length of about 8.5 centimetres (3.3 in) and features distinctive red eyes and a broad dark vertical 'waistband' with scattered red spots toward the tail. It is considered to be of low vulnerability, and is distributed throughout much of the western Pacific Ocean, from Java to Fiji, and from the Ryukyu Islands south to the Great Barrier Reef. The male pajama cardinalfish incubates the eggs in its mouth until they hatch.