Nanmatsu et al. Reproductive biology of Dexistes nkuzenius 



641 



Table 3 



Annual changes in the composition of female Rikuzen sole oocytes in each maturity phase. Some maturing and spent ova- 

 ries contained ovulated but not spawned oocytes. Such ovaries were included under "Number of samples with atretic oocytes." 

 Developmental oocyte stages were abbreviated as follows: EP=early perinucleolus, LP=late perinucleolus, CA=cortical alveoli, 

 PY=primaryyolk,SY=secondary yolk, TY= tertiary yolk, MN=migratory nucleus, PM = prematuration,POF=postovulatory follicle. 



Year Month 



EP LP 



CA 



PY 



SY 



TY 



MN 



PM 



POF 



Maturity phase 



Number of 

 samples with 

 atretic oocytes 



2000 Mav 



Jun 



Jul 

 Aug 



early Sep 



late Sep 



Oct 



Nov 



Dec 



continued 



Those in the large-diameter group were regarded as 

 advanced yolked oocytes that would be spawned in the 

 next reproductive season and were used for estimations 

 of potential fecundity. Potential fecundity varied widely 

 among individuals from 24,765 (114 mm SL) to 393,212 

 (204 mm SL) eggs (an average of 161,340 ±90,688 eggs 

 (165 ±25 mm SL)). Potential fecundity (PF) was posi- 



tively correlated with body size and the relationship was 

 expressed by the following equation: 



PF=0.000235SL 3 



(Fig. 6). 



Potential fecundity and relative fecundity (poten- 

 tial fecundity /eviscerated body weight) increased with 



