Several species of hippolytid shrimp of the genus Lysmata are
described as protandrous hermaphrodites, with speculation that some Lysmata
are simultaneous hermaphrodites and/or store exogenous sperm. The objective
of this study was to ascertain the presence of simultaneous hermaphroditism in
L. amboinensis De Man. For this experiment, four pairs of female-phase L.
amboinensis were isolated until each shrimp spawned two fertile clutches of
eggs. For two of the four pairs, pair-mates were then separated and isolated in
an identical fashion. Paired individuals continued to spawn and hatch fertile
eggs. Isolated individuals spawned only infertile eggs. Paired shrimp also
synchronized their molt cycles in a staggered fashion, such that individuals alternated
sexual roles. Histological and morphological examination shows that
each female-phase individual possessed an active male and female portion of
the gonad with corresponding gonoducts. The results indicate that this species
is a functional, simultaneous hermaphrodite. Previously, this pattern has not been adequately described in any decapod crustacean