Occurrence of additional Zoea-VI larvae in the mud
crab, Scylla paramamosain (Estampador), reared in the laboratory
Ch.
Zeng, S. Li, H. Zeng-2004
Hydrobiologia,
529(1): 49-58
Abstract:
Mud
crabs, Scylla spp. , are commercially important in many
Indo-Pacific countries. The larval development of mud crabs has been
reported previously as five zoeal and one megalopal stages. This paper
reports larval rearing experiments that revealed variability in larval
developmental stages in the mud crab Scylla paramamosain, one of
four mud crab species. In addition to normal five zoeal stages, an
alternative pathway of developing through six zoeal stages was observed for
the crab. There were evidences suggested that the appearance of the
additional Zoea-VI larvae was associated with unfavourable dietary
conditions, including poor quality of diet, inadequate quantity of dietary
supply and a period of starvation for newly hatched larvae. Based on exuviae
and larval specimens, the morphology of the additional Zoea-VI larvae was
described.
(Department of Oceanography, Xiamen University, Fujian, P.R.China)