Can you find a square spot on any of the fish? The squarespot anthias is a small marine fish that inhabits coral reefs in the western and southwestern Pacific Ocean. The species occurs in a range of brilliant colors including red, orange yellow and purple. Typically, the male has a large magenta patch on its sides just behind the gill cover.

This anthias typically occurs in aggregations of many females and fewer males. Such groupings can contain as many as a thousand individuals, which are usually made up of smaller groups or “harems” consisting of one male and up to twenty females. The squarespot anthias can change gender from female to male due to environmental or social factors. Anthias begin life as females and become males under the appropriate conditions, such as when the male in charge of the harem dies. This process ensures that there will always be representatives of both sexes to provide for reproduction.

You can find this anthias and others in one of the largest reef exhibits in the world in the Tropical Diver gallery.

• This fish comes in a variety of colors including red, pink, orange, yellow and purple.
• The squarespot anthias lives in large groups. The numbers in a single school can be in the thousands.
• These groups are found in areas of branching corals where they are able to find shelter as well as a place to rest at night.
• The schools are made up of smaller groups which are called harems. Each harem has one male and approximately six to twenty females.

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