Common name: Narrowstripe cardinalfish

Scientific name: Pristiapogon exostigma (Jordan & Starks, 1906)
Eyeshadow cardinalfish (Apogon exostigma)Narrowstripe cardinalfish
Tropical Pristiapogon exostigma fish underwaterEyeshadow cardinalfish (Apogon exostigma)

General information

The Blackaxil Cardinalfish, scientifically known as Pristiapogon exostigma, is a small and peaceful marine fish that is well-suited for the home aquarium. Its distinctive feature is the black spot located at the base of the tail, which gives it the name 'twospot'. This species is part of the Apogonidae family, which is known for its hardiness and ease of care, making it a popular choice among both novice and experienced aquarists.

Details

Recommended minimum tank volume
150 liter (40 gallons)
Salinity
S.G. 1.020 to 1.025
Temperature
22 to 26 °C (72 to 79 °F)
Acidity
pH 8.1 to 8.4
Average size
10 cm (4″)
Care level
Moderate to easy Prefers dimly lit aquariums
Diet
Planktivore Feeds on zooplankton in the wild
Social
School Best kept in groups of 6+
Reefsafe
Yes
Aggression
Peaceful
Captive bred
No

Taxonomy

  1. Kingdom
    Animals
    Animalia
  2. Phylum
    Chordates
    Chordata
  3. Class
    Ray-finned Fishes
    Actinopterygii
  4. Order
    Perch-like Fishes
    Perciformes
  5. Family
    Cardinalfish
    Apogonidae
  6. Genus
    Cardinalfish
    Pristiapogon
  7. Species
    Narrowstripe cardinalfish
    Pristiapogon exostigma (Jordan & Starks, 1906)
  8. Synonyms
    Amia exostigma Jordan & Starks, 1906
    Apogon exostigma (Jordan & Starks, 1906)
    Apogon frenatus Lachner, 1953

Care

Blackaxil Cardinalfish are relatively easy to care for. They thrive in a well-established aquarium with stable water conditions and plenty of hiding spaces. These fish are nocturnal and prefer dimly lit environments. They are not aggressive and can be kept with other peaceful fish. A varied diet of small meaty foods such as mysis shrimp, brine shrimp, and finely chopped seafood will help maintain their health and coloration.

Reproduction

Like many cardinalfish, Pristiapogon exostigma is a mouthbrooder. The male will carry the fertilized eggs in his mouth until they hatch, which provides protection from predators. This fascinating reproductive behavior can sometimes be observed in the home aquarium, offering a unique spectacle for the aquarist.

Habitat

The Blackaxil Cardinalfish is found in the Indo-Pacific region, from the Red Sea and East Africa to Samoa, north to the Ryukyu Islands, and south to New Caledonia. They typically inhabit coral reefs and lagoons, often hiding among the branches of corals or in crevices during the day.