Spotfin Butterflyfish
Bold, bright, and easy to care for, the Spotfin Reef Butterfly is named for the small, black spot located on the end of the dorsal fin. Adults are white, with bright yellow pelvic and caudal fins, and a narrow yellow bar from the gill to the base of the pectoral fins. A vivid black, vertical bar on the head passes through the eye. Juveniles exhibit an added dark spot at the base of the anal fins with a shadowy streak that extends to the small spot on the dorsal fin.
What really sets the Spotfin Reef Butterfly apart is at night, this fish undergoes remarkable changes. The large, dusky smudge on the dorsal fin becomes black and broad, and dark bands appear on the body. It is also known to sometimes swim upside down, and occasionally squirt water like fountain above the waterline.
| Features | Details |
|---|---|
| Color Pattern | White body, yellow pelvic and caudal fins, narrow yellow bar from gill to pectoral base, black vertical bar on head |
| Size | Up to 4 inches (10 cm) |
| Behavior | Active during day, changes appearance at night; may swim upside down or squirt water |
| Lifespan | Up to 10 years |
FAQ
What are the distinguishing features of the Spotfin Butterflyfish?
Adults have a white body with bright yellow pelvic and caudal fins, a narrow yellow bar from the gill to the base of the pectoral fins, and a vivid black vertical bar on the head. A small black spot is located on the end of the dorsal fin. Juveniles have an additional dark spot at the base of the anal fin with a shadowy streak extending to the dorsal fin spot.
Does the Spotfin Butterflyfish change appearance at night?
Yes, at night the fish undergoes noticeable changes: the dusky smudge on the dorsal fin becomes black and broad, and dark bands appear on the body. It may also swim upside down or squirt water like a fountain above the waterline.
What is the typical size and lifespan of this fish?
The Spotfin Butterflyfish grows up to 4 inches (10 cm) in length and can live up to 10 years under proper care.
Molly Mackenzie –
The Spotfin Butterflyfish is a striking addition to my reef tank. It’s active during the day and shows a fascinating transformation at night. The black dorsal band and body markings are very noticeable. It swims in a unique way and occasionally squirts water, which is both entertaining and unusual. Easy to maintain and fits well in a medium-sized reef setup.
Joanne Miller –
I’ve had this fish for six months and it’s become a highlight of my tank. The coloration is vibrant and the nighttime behavior is quite captivating. It swims upside down occasionally, which is rare and adds to the charm. I do notice it’s more active in the evening, so I keep the lights dimmed then.
Rebecca Chapman –
This fish is beautiful and very easy to care for. The yellow fins and black markings stand out in the tank. At night, it changes dramatically—dark bands spread across its body and the dorsal fin becomes broad and black. I love the unique behavior and the way it interacts with other fish in the tank.