Description: Lookdown fish have laterally flat, reflective bodies with a steep forehead and protruding lower jaw. The silvery coloring comes from guanine pigments. The pigmentation creates the mirror-like body but can be manipulated to highly reflect light or dim the light, depending on what will best camouflage them in the water. On the second dorsal fin, the first rays length extends to reach the deeply forked tail. The common name comes from its peculiar head structure. Juveniles have light, vertical stripes that disappear with age.
Size: This species can reach lengths of about 19 inches (48.3 cm) and weigh up to 4.5 pounds (2 kg).
Behavior: Selene vomer are highly adaptable, living in salt and brackish waters, and travel in large groups called shoals. The body shape allows them to be quick and agile during the pursuit of prey or flight from predators. Migration occurs at particular times of the year for breeding, winter and hibernation.
Diet: Their diet consists mainly of benthic crustacean, worms, small crabs and fish.
Senses: The eyes do not have any type of adipose (transparent) eyelid which is believed to be used for protecting the eye or as a lens that aids in focusing on an object.
Communication: When feeling threatened or under stress, the swim bladder and teeth are used to make loud grunts.
Reproduction: Spawning is believed to occur further offshore during the summer. Females release pelagic eggs into the water column where males then fertilize them. Larvae are also believed to develop in areas further offshore.
Habitat/range: These fish inhabit shallow coastal waters with hard or sandy bottoms in the Tropical Atlantic and the Gulf of Mexico and is common along the Texas coast.
Status: Lookdown fish have not been evaluated by the IUCN Red List of Threatened Species.