The spotfin lionfish is similar to the red lionfish.
It differs in the characteristic appendages over each eye and similar to antennae, which gave it its species name. Additionally, its dorsal and pectoral fins are formed of very long, free-moving white spines, and it is the only lionfish to feature the colour blue.
The spotfin lionfish feeds on crabs and shrimp, which it hunts by night in lagoons. To trap its prey, it fans out its pectoral fins as far as possible. By day, it takes shelter in rocky or coral crevasses, where it rests against the vertical wall or upside down, with its head toward the floor.
This species is oviparous (egg-laying). Each female can spawn several tens of thousands of eggs. The larvae hatch a few days later and drift in the current for several weeks. Each ray of its dorsal, anal and pelvic fins is connected to a venom gland. Its sting is very painful but rarely fatal to humans.