Threadfin Butterflyfish Care Guide
Chaetodon auriga · Saltwater Butterflyfish
What Threadfin Butterflyfish look like
The Threadfin Butterflyfish (Chaetodon auriga) exhibits a distinctive laterally compressed body, reaching a maximum adult size of approximately 7 inches (18 cm). Its coloration is predominantly yellow with a prominent black 'thread' extending from the dorsal fin, which is particularly pronounced in males, showcasing sexual dimorphism. The fins are elongated, with the dorsal fin featuring 12-14 spines and 18-20 soft rays, while the anal fin comprises 3 spines and 17-19 soft rays. The species possesses a small mouth equipped with specialized dentition, adapted for feeding on small invertebrates and coral polyps. Notable defensive adaptations include its ability to blend into the reef environment, aided by its vibrant coloration and the presence of a black spot near the eye, which may confuse predators.
Behavior & temperament
Threadfin Butterflyfish are generally found in pairs or small groups, exhibiting a social hierarchy where dominant individuals establish territories within their habitat. They are primarily mid-water swimmers, often seen hovering near coral reefs. Breeding behavior involves elaborate courtship displays, where males perform a series of synchronized movements to attract females. Their temperament is generally peaceful, although they can exhibit territorial aggression towards other butterflyfish species. They are known to be relatively shy, often retreating into crevices when threatened.
Diet & feeding
In the wild, Threadfin Butterflyfish primarily feed on coral polyps, small invertebrates, and algae, making them obligate corallivores. In captivity, they require a varied diet that includes high-quality frozen or live foods, such as brine shrimp, mysis shrimp, and specialized coral foods.
Behind the name
The genus name 'Chaetodon' is derived from the Greek words 'chaite' meaning 'hair' and 'odon' meaning 'tooth', referring to the hair-like structures on the teeth of these fish. The species name 'auriga' is Latin for 'charioteer', possibly referencing the fish's vibrant coloration and graceful swimming style.
Plan your tank
Check the numbers before you buy: tank volume, salinity, salt mix, water changes, and your ongoing care routine.
Keeping Threadfin Butterflyfish?
AquaLens identifies your fish and plants from a photo, tracks water chemistry, and flags health issues early — free on iOS and Android.
