This is a slightly misleading interpretation in an undifferentiated gonochorist
species such as the zebrafish, because males that have arrested sexual differentiation, while superficially resembling early ovary type tissue (as do both sexes at this stage), do not develop into functional females and their gonads will differentiate into testes when removed from exposure (Hill and Janz 2003).
However, a recent study of the green humphead parrotfish (Bolbometopon muricatum) has emphasised that a definitive conclusion as to whether certain species in this family are protogynous hermaphrodites or gonochorists
can be difficult to ascertain, even when there is detailed information on such features as the size compositions of the two sexes and the histological characteristics of their gonads (Hamilton et al.
The sexuality of pectinids ranges from strictly gonochorists
to functional hermaphrodites (Coe 1945, Reddiah 1962), and there are 2 types of follicular structure in hermaphroditic specimens (Coe 1945, Reddiah 1962, Gaspar-Soria et al.
A three-year study (1998-2000) into its reproductive biology within the Tsitsikamma National Park revealed that these fishes are serial spawning late gonochorists.
as hermaphrodites) they mature as either a male or female (Table 1) and are therefore late gonochorists (rudimentary hermaphrodites).