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A bright orange squarespot with it's hot pink spot on the side swimming horizontally

Squarespot

Pseudanthias pleurotaenia

Not on exhibit
Animal type
Fishes
Ecosystem
Coral reefs
Relatives
Groupers, fairy basslets; Family: Serranidae
Diet
Tiny drifting animals
Range
West-central Pacific from Australia to southern Japan; throughout Micronesia
Size
Up to 3.9 inches (10 cm)

Meet the squarespot

By day, these brilliantly colored fish gather in small groups just above the edges of steep reef slopes. Here, strong currents provide a steady supply of the tiny, drifting animal plankton on which they feed. By night, or when larger predators threaten, squarespots seek shelter among the nooks and crannies of the reef.

Status: Least concern

Least concern(active)

Near threatened

Vulnerable

Endangered

Critical

Extinct in wild

Extinct

Did you know?

Only males sport the bright, square spots on their sides that give this fish its common name. Squarespots are most common at depths of around 100 feet (30 m) or more. There in the dim light their spots seem to glow, warning rival males and catching the eye of females.

Conservation

In some places unscrupulous collectors use cyanide, bleach and other chemicals to catch reef fishes for the pet trade. These poisons can kill fishes, corals and other reef life. Fishermen in the South Pacific and Southeast Asia often dynamite reefs to kill fishes for food. The blast stuns the fishes, which then float to the surface where they can be easily scooped up. But the explosions destroy the reefs and kill many more animals than just those taken for food.

Cool facts

  • In addition to the bright spots on their sides, males perform acrobatic swimming displays to mark their territories and attract mates.
  • All squarespots start life as females. As they grow, some change into males.

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