The scarlet frogfish is an ambush predator that lives on rocky and coral reefs of the Indian and Pacific oceans. It is an absolute master of disguise and is very difficult to find on the reef surface. This species exhibits a wide variety of color morphs, based on location across its range, and oftentimes even two individuals that live on the same reef can look quite distinct. Individuals of this species spend almost all of their time in constant contact with the reef surface, resting and crawling on the modified fins that resemble legs. These “legs” give the frogfishes their common name.
The scarlet frogfish, like all frogfishes, is an anglerfish. Most anglerfishes (e.g., the humpback anglerfish) live in the deep sea, but the frogfishes comprise a family of shallow-water representatives of this large group of interesting fishes. The frogfishes have small fishing lures, made from modifications of their dorsal fins, which they use to attract small fishes. The scarlet frogfish remains almost perfectly motionless, for long periods at a time, moving only its lure. Once a potential target comes close enough, it lunges toward the prey, rapidly opening its jaws, and creating enough suction to swallow the prey whole. The scarlet frogfish’s ability to blend in with its surroundings and remain perfectly motionless are both effective means of avoiding predation. This species is almost never eaten by predators.
Scarlet frogfish are typically solitary, only coming together to form pairs when mating. After a male successfully courts a female, the pair reproduces via a behavior known as broadcast spawning. The female rapidly swims above the reef surface to release her eggs higher in the water column, and the male follows quickly behind, releasing his sperm. This method increases the likelihood that eggs will become fertilized and that fertilized eggs will not be eaten by egg predators on the reef surface.
This species is not commercially valuable and is not accidentally captured by fisheries targeting other species. Though some individuals are occasionally captured alive for display in public and private aquaria, this uncommon practice is not a threat to scarlet frogfish populations. Scientists have not officially assessed the conservation status of the scarlet frogfish, but this naturally rare species is likely a species of least conservation concern.