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Bluehead Wrasse

Thalassoma bifasciatum


This individual is a terminal phase male, or "supermale". The blue coloration on the head of this fish is only found in the males. Young males and females are typically yellow and white. Terminal phase males typically measure 70 to 80 mm in length.


Native to the Caribbean Sea. Inhabits reef areas, inshore bays and seagrass beds.

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Maria dB
Maria dB 9 years ago

That is really interesting - thanks for the explanation!

marylou.wildlife 9 years ago

Maria, all wrasse species are born female. Wrasses are protogynous hermaphrodites, meaning females transition to male in the wild as harem conditions and space require. During transition, the females go through two primary phases... initial phase male and terminal phase male. At the terminal phase, a full transition has been completed and the fish is 100% male. Up until that point, they are in an initial phase. In a harem, they will only be one terminal phase male, which is essentially the alpha male.

Maria dB
Maria dB 9 years ago

Does the term "terminal male" mean it will soon die?

Spotted by


Spotted on May 18, 2013
Submitted on Aug 8, 2013

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