Auriga Butterflyfish Identification Guide
Recognize the Auriga Butterflyfish by its crosshatched pale body, black eye bar, and trailing filament on the dorsal fin.
Read the full Auriga Butterflyfish encyclopedia entry →
Key identification features
- Oval, laterally compressed body up to about 23 cm
- Pale yellow-white body covered in a fine diagonal crosshatch pattern
- Black bar crossing the eye
- Black spot on the rear soft dorsal fin, though this spot is faint or absent in some Indian Ocean populations
- Long, thread-like filament trailing from the tip of the soft dorsal fin in adults, giving rise to the alternate name Threadfin Butterflyfish
- Yellow wash across the rear body, dorsal, anal, and tail fins
Common look-alikes
- Vagabond Butterflyfish (Chaetodon vagabundus): shows two dark bars near the tail rather than a single dorsal spot, chevron-style striping instead of crosshatching, and no trailing dorsal filament.
- Threadfin populations without a dorsal spot can be confused with plain crosshatched species, but the elongated dorsal filament remains a reliable adult mark regardless of spot presence.
Where you'll see one
This is one of the most widespread butterflyfish, found from the Red Sea across the Indo-Pacific on lagoons, reef flats, and seaward reefs, thriving as an adaptable generalist feeder on coral, algae, and small invertebrates.
Frequently asked questions
How do I tell an Auriga Butterflyfish from a Vagabond Butterflyfish?
Look near the tail: the Auriga Butterflyfish has a single black spot on the rear dorsal fin and a trailing dorsal filament, while the Vagabond Butterflyfish shows two dark bars near the tail base and no filament.
Why might an Auriga Butterflyfish lack the black dorsal spot?
Some populations, particularly in the Indian Ocean, naturally lack or show only a faint version of the dorsal spot, so the long trailing filament on the soft dorsal fin is the more consistent identifying feature in adults.