The Pajama Cardinalfish (Sphaeramia nematoptera), also known as the Spotted Cardinalfish, Coral Cardinalfish, or Polkadot Cardinalfish, is a species of fish belonging to the family Apogonidae. It is a popular aquarium fish.

Distribution and Habitat

The Pajama Cardinalfish is distributed throughout much of the western Pacific Ocean from Java to Fiji, and from the Ryukyu Islands south to the Great Barrier Reef.

Physical Description

The Pajama Cardinalfish grows to a total length of approximately 8.5 cm (3.3 in). It features distinctive red eyes and a broad dark vertical waistband with scattered red spots toward the tail. It has greenish-yellow faces, bright orange eyes, and silver-based bodies dressed with a bold black scalar margin and posteriors dotted with orange polka dots.

Diet and Feeding

In the wild it feeds on small crustaceans and plankton. In captivity it readily accepts a varied carnivorous diet including mysis shrimp, brine shrimp, and prepared foods.

Behavior and Reproduction

The Pajama Cardinalfish is a mouthbrooder. The male incubates the eggs in his mouth until they hatch. The Pajama Cardinalfish is peaceful and can be kept in groups. It forms a strict hierarchy when kept in small groups.

Aquarium Care

It requires a tank of at least 30 gallons with abundant live rock for hiding. It is considered reef-safe.

Conservation Status

Classified as Least Concern by the IUCN Red List.