Dragonet

See text Dragonets are small percomorph marine fish of the diverse family Callionymidae (from the Greek kallis, "beautiful" and onyma, "name") found mainly in the tropical waters of the western Indo-Pacific.

However, male dragonets can be differentiated from the goby by their very long dorsal fins, and females by their protruding lower jaws.

Dragonets have flattened, triangular heads with large mouths and eyes; their tail fins are fan-shaped and tapered.

[2] The fish's spawning behavior is divided into four distinctive stages: courtship display, pairing, ascending, and the release of eggs and milt.

Males will sometimes also spread their dorsal fins, repeatedly open and close their mouths, and position themselves on top of the females and rub their abdomens with their bodies.

[4] Prior to spawning, a male and female dragonet pair will ascend approximately 0.7-1.2 meters up a water column from the sand at the bottom of the ocean.

[5] The pair rises slowly up the water column, moving in a semicircular manner by swimming with their pectoral fins.

[7] As a result of this behavior, male dragonets suffer higher mortality rates than females do after attaining maturation.

Males have evolved larger bodies, as well as longer spines and rays, in order to achieve dominance in reproduction.

The fish feeds entirely on benthic sources, primarily copepods, amphipods, and other small invertebrates living on blades of sea grass.

All of them feed by extending their highly protractible jaws toward their food and drawing it into the mouths, frequently followed by the expulsion of sand.

Individuals do not defend specific areas of substrate, as well as any resources that might be present on them, from intrusion by conspecifics or other fish species.

[7] Among Calliurichthys japonicus and Repomucenus huguenini, the two most abundant dragonet species, amphipods are the most plentiful prey during the spring and winter months.

[7] In defense against its predators, the dragonet rapidly buries itself under the sand at the bottom of the ocean so that only its eyes remain visible.