Blackfin Clownfish

The Blackfin Clownfish (Amphiprion nigripes) is a species of anemonefish in the family Pomacentridae, endemic to the central Indian Ocean, primarily the Maldives and Sri Lanka. It is closely related to the Skunk Clownfish complex but is distinguished by dark, near-black lower fins that give the species its common name. Like other anemonefish, it lives in an obligate symbiosis with host sea anemones, relying on the anemone's stinging tentacles for protection while itself protected by a specialized mucus coating. Its restricted geographic range makes it one of the more range-limited clownfish species, and it is a signature reef fish for divers visiting Maldivian and Sri Lankan reef systems.

• Body: oval, orange to orange-red, 8-11 cm at maturity
• Marking: a single white bar just behind the eye, with no other body bars
• Fins: pelvic and anal fins dark, near-black to deep purple, contrasting sharply with the orange body; dorsal and caudal fins remain orange
• Head: rounded with a moderate-sized eye

The combination of a single head bar and darkened lower fins separates it from the very similar Skunk Clownfish, which lacks a head bar and instead shows a dorsal stripe. Its geographic restriction to the Maldives and Sri Lanka also helps confirm identification, as few other anemonefish share this exact range.

Blackfin Clownfish are endemic to the central Indian Ocean, found almost exclusively around the Maldives and Sri Lanka. They inhabit clear coral reef lagoons and outer reef slopes at depths of about 2-20 meters, in water typically between 26-29°C. As with all anemonefish, distribution is tied to the presence of a suitable host anemone, most often the magnificent sea anemone or merten's sea anemone, on reef flats and slopes with good visibility and moderate current.

Blackfin Clownfish live in small social groups anchored to a single host anemone, with a size-based hierarchy topped by a dominant breeding female and a subordinate breeding male. As protandrous hermaphrodites, all individuals begin life as males, with the largest fish able to transition to female if the group's female is lost. Eggs are laid on cleared substrate at the anemone's base and guarded by the male until hatching. The species shows strong site fidelity to its host anemone and displays territorial chasing behavior toward intruders that approach too closely, a trait shared broadly across the anemonefish group.