Stegastes

Biology and range

These damselfish feed mainly on filamentous algae, which makes up about 90% of their diet.^[4] The genus includes species that vary in size, with S. acapulcoensis reaching up to 17 cm and S. pictus only 7.5 cm, and all have deep, laterally compressed bodies and forked tails.^[1] The lateral line is incomplete, featuring gaps along its course.^[5] Coloration depends on the species and can also differ across various parts of a fish's geographic distribution.^[5]

Young individuals often display vivid colors that are entirely unlike the coloration of mature fish of the same species; for instance, the brown hue of Stegastes apicalis results from melanosomes containing pheomelanin, a pigment not typical of most fish.^[5] These fish defend patches of algae they cultivate, aggressively keeping other fish away from their tended gardens.^[4] While most Stegastes species are solitary, some form pairs with a mate or gather in small, loose groups.^[4] Their territorial nature makes most species highly aggressive, and they will attack any intruder, including biting at divers who come too close.^[6]

What the specialist sources record

The World Register of Marine Species records Stegastes otophorus as an accepted species in the family Pomacentridae, with a marine and brackish environment.^[3] GBIF also accepts Stegastes otophorus, placing it in order Perciformes and family Pomacentridae, and holds 45 occurrence records for this taxon as of 7 October 2026.^[7]