Ctenodactylus

Ctenodactylus is a genus of marine ray-finned fish belonging to the family Ctenodactylidae. The genus is native to the tropical and subtropical waters of the Indo-Pacific region, with species ranging from the Red Sea to Australia and as far east as Hawaii. Ctenodactylus species are known for their distinctive, flattened bodies and elongated, serrated dorsal and anal fins, which are used for swimming and capturing prey.

The genus includes several species, with the most well-known being Ctenodactylus valentini, commonly known as the Valentine's Day fish due to its vibrant red and white coloration, which is most pronounced during the breeding season. Other species include Ctenodactylus bicolor, which is characterized by its two distinct color phases, and Ctenodactylus labialis, known for its elongated snout and large, fang-like teeth.

Ctenodactylus species are typically found in shallow, coral reef environments, where they feed on small crustaceans and other invertebrates. They are oviparous, with females laying demersal eggs that are guarded by the male until they hatch. The genus is of particular interest to ichthyologists due to its unique morphology and behavior, as well as its potential as a model organism for studying fish evolution and development.