Reproductive biology of the spiny lobster
Panulirus japonicus was histologically examined by
monthly sampling between March 1993 and September 1994 at Oshima Island, near
Tokyo. P. japonicus had a well defined reproductive
cycle. Yolk accumulation became manifest in February and ovaries grew rapidly
in March. Females spawned from late April to mid August and were ovigerous to
mid September. Of large females with a carapace length (CL) of ≥47 mm,
93% were estimated to spawn twice during the spawning season. Size at
which 50% of females reached sexual maturity was estimated to be 41.8
mm CL, as calculated from a logistic model. Some individuals considered to be
primiparous showed delayed vitellogenesis and were estimated to spawn only
once during the season.
A revision of the Indo-West Pacific spiny lobsters of the Panulirus japonicus group