Anthias Identification Guide
Recognize anthias by their schooling habit, forked tails, and vivid orange-to-purple colors that differ between males and females.
Read the full Anthias encyclopedia entry →Key identification features
- Small, slender basslets generally 2-4 inches long
- Bright coloration in shades of orange, pink, magenta, or purple depending on species
- Deeply forked, often lyre-shaped tail fin
- Dominant males are larger with elongated fin filaments and a bold color patch on the dorsal fin
- Females are smaller, more uniformly colored, and far more numerous than males in a group
Common look-alikes
- Fairy basslets and small groupers (Liopropoma spp.) can share similar coloring but are solitary and secretive, never forming open shoals.
- Wrasses of similar color are more elongated and swim with a distinctive pectoral-fin "rowing" motion rather than the anthias' hovering style.
- Behavior is the giveaway: true anthias are almost always seen in large midwater aggregations, unlike solitary basses or wrasses.
Where you'll see one
Anthias hover in large shoals over steep outer-reef drop-offs and current-swept slopes, feeding on drifting plankton by day and retreating into reef crevices at night. They are found throughout the Indo-Pacific and Red Sea, with a handful of related species in the tropical Atlantic.
Frequently asked questions
How do I tell a male anthias from a female of the same species?
Males are typically larger, carry longer trailing fin filaments, and display a distinct color patch or elongated dorsal ray that females lack.
How do I know I'm looking at anthias and not another reef fish?
Anthias almost always appear in large hovering shoals over reef drop-offs, feeding on plankton in midwater, a habit that sets them apart from solitary reef basses.