NEWS102
24
Marines
Paracheilinus filamentosus
,male.Themajorityof speciesof thisgenusgrow toaround8 cm long.
lmost all wrasses have several color
phases that look extremely different
and have frequently led tomales, females,
and juveniles being scientifically described
asdifferent species.Theentire family is thus
very difficult to classify and we are still a
long way from really understanding the
wrasses.
Threesexes?
Obviouslythereare fundamentallyonlytwo
sexes:maleand female.Onecanchoose to
speak of functional hermaphrodites, that
is animals that produce both eggs and
sperm simultaneously, as a third sex; but
that isn’twhat ismeant here and it is also
A
The wrasses (Labridae) are a very successful family of fishes, withmore
than 500 species.They are exclusivelymarine; a number of species occur
in brackishwater but none lives there permanently. Andwrasses have a
third sex....
Verydifferent sexes–
wrasses
byMatthiasReising
Paracheilinus filamentosus
, female
Paracheilinuscarpenteri
,male
Paracheilinuscarpenteri
, female
fairly rare in fishes (there are some,
however, for example among thegrouper
family, the Serranidae). No, matters are
quite different withwrasses; in their case
sex is genetically determined right from
the start, so that thereare individuals that
aremales from the time of hatching, and
others that are females.This isn’t apparent
though, as males and females look the
sameas juveniles.But, juveniles alsooften
look very different to adults! So we can
straightaway check off the first color
phase, the juvenilephase.
With the onset of sexual maturity
juveniles develop intoprimarymales and
primary females. Again both very often
look very different and the color change
from juvenile to sexually active fish also
