The type of fish or Grouper which reproduce when they are around 20 years old is called monandric protogynous hermaphrodites.
The Groupers is a type of fish that is characterized by a large mouth and stout body.
They belong to the subfamily of <em>Epinephelinae</em>.
These groupers are known as monandric protogynous hermaphrodites because they mature to become only females which changes their sexes after sexual maturity.
This change in sex of the fish depends on internal or external triggers.
These reproductive changes usually occurs around 20 years of age in a groupers.
Therefore, the type of fish or Grouper which reproduce when they are around 20 years old is called monandric protogynous hermaphrodites.
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