
Banggai Cardinalfish
Pterapogon kauderni
Ostorhinchus aureus

The ringtail cardinalfish spends its days tucked into a crevice, waiting for dark before it comes out to hunt. Its coppery body and bold face markings make it one of the easier cardinalfish to pick out once you know what to look for.
Also known as: ringtailed cardinalfish, ring-tailed cardinal-fish, ringtail cardinal, ring-tailed cardinalfish, ring-tail cardinalfish, golden cardinalfish, bandtail cardinal
This species is easily confused with another cardinalfish, Ostorhinchus fleurieu. Check the black bar at the base of the tail: on this species it narrows in the middle, and the dark stripe from snout to eye is already there in juveniles, not just adults.
This fish has a coppery body with a broad blackish bar at the base of its tail. A narrow blue streak runs along the upper jaw, and a broad blackish stripe runs from the tip of the snout to the eye.
By day it hides in holes in rocks or under ledges in shallow water, often on reefs across the Red Sea, East Africa, and the tropical Indo-Pacific as far as Japan and Australia. It sometimes gathers in mixed groups with the similar Ostorhinchus apogonoides during summer and autumn, splitting into separate groups the rest of the year.
In summer and autumn this species often forms mixed groups with another cardinalfish, Ostorhinchus apogonoides, then splits off to form its own separate groups again in winter and spring.
Describe what you saw and we name it, then keep every species you find in your Oceandex.