Description: Threadfin snappers have a yellow body with bright blue lines that run horizontally and two black vertical lines on the head. They also have an orange stripe that crosses the eyes, one across the back of the head and a dark caudal spot. Juveniles have a black stripe that runs laterally from the eyes to the tail that fades with maturity and are replaced by a series of blue lateral lines.
Size: This species reaches a maximum length of about 24 inches (61 cm).
Behavior: Symphorichthys spilurus is a solitary species that only come together with its own species to spawn. They are shy, aggressive fish that enjoy hiding but are active during the daytime and less at night.
Diet: Their diet consists of mainly fish, crustaceans and mollusks.
Communication: One form of communication for this fish species is special movements, such as males darting in every direction when trying to attract a female before spawning. Females see the males performance and then know the males are ready to breed.
Reproduction: Before breeding, schools aggregate in large crowds where spawning chases begin. Males turn almost black and females become very pale in color. Females bellies will swell, showing it is time for spawning and they release gametes into the water. The eggs are then fertilized by males. The preferred area to spawn is seaward reefs
Habitat/range: Threadfin snappers have a wide distribution in the Indo-Pacific, especially Australia, where they can be found over sand and rubble areas of coastal reefs abundant in coral. Adults prefer deeper waters and juveniles usually stay in more shallow areas.
Status: Have not been evaluated by the IUCN Red List.