Most species of labroids are protogynous and sexually dichromatic, with at least 2 color morphs "” a usually drab-colored "˜initial phase' (IP, either female or female and precocious male), and a brighter-colored "˜terminal phase' (TP) male (Robertson & Warner 1978, Warner & Robertson 1978).
In some lineages of protogynous fishes, 2 types of males occur: in some groups males are monandric (all derived from sex-changed females), whereas in other groups (like most scarinine parrot-fishes of the genera Scarus and Chlorurus : Robertson et al. 1982), males are diandric, i.e. derived from either undifferentiated juveniles or from sex-changed females.
With few exceptions, changes in coloration and sex are synchronous in scarids (Choat & Robertson 1975, Bruce 1980); less is known about sex and color change syn-chronicity in labrids (Warner & Robertson 1978, Moyer 1991)
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