The ring-tailed cardinalfish (Apogon aureus) is a widespread fish species in the family Apogonidae.

Range

Red Sea

Red Sea

The Red Sea is a seawater inlet of the Indian Ocean, lying between Africa and Asia. The connection to the ocean is in the south through the Bab el Mandeb strait and the Gulf of Aden. In the north, there is the Sinai Peninsula, the Gulf of Aqaba, and the Gulf of Suez...

 and East Africa

East Africa

East Africa or Eastern Africa is the easterly region of the African continent, variably defined by geography or geopolitics. In the UN scheme of geographic regions, 19 territories constitute Eastern Africa:...

 to Papua New Guinea

Papua New Guinea

Papua New Guinea , officially the Independent State of Papua New Guinea, is a country in Oceania, occupying the eastern half of the island of New Guinea and numerous offshore islands...

, north to Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

, south to Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

.

Description

This fish is coppery-coloured with a broad blackish bar at the base of the tail up to 14.5cm in length. The upper jaw has a narrow blue streak, and a broad blackish stripe extends from the front of the snout to the eye

Eye

Eyes are organs that detect light and convert it into electro-chemical impulses in neurons. The simplest photoreceptors in conscious vision connect light to movement...

. Easily confused with Apogon fleurieu, where the black tail bar does not narrow in the centre, but unlike this species the stripe is also present in juveniles.

Habitat

Apogon aureus inhabits holes in rocks or under ledges in shallow waters. It is known to occur in mixed aggregates with Apogon apogonoides during summer and autumn, but form separate aggregates in winter and spring.