Baelde: Biology and dynamics of reproduction in Hyperoglyphe antarctica 



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Table 1 



Female and male blue-eye trevalla, Hyperoglyphe antarctica. maturity stages based on macroscopic and histological examina- 

 tion. Adapted from Hunter and Macewicz ( 1985, a and b); Schaefer ( 1987); West ( 1990); Hunter et al. (1992); Davis and West ( 1993). 



Females 



Stage 



Macroscopic description 



Histological description 



Oocyte development 



1 Immature 



2 Early developing 



3 Developing 



4 Late developing 

 (yolked) 



5 Ripe 



6 Running-ripe 



7 Spent 



Small thread-like ovaries, pink 

 and translucent; 



Oocytes not visible, ovaries pink 

 and translucent; 

 First-time developing females: 

 ovaries up to 10 cm long, 1 cm 

 across, ovary wall thin and trans- 

 parent; 



Redeveloping females: ovaries up 

 to 20 cm long, 5 cm across, flac- 

 cid, ovary wall thick, whitish, 

 and opaque; 



Small oocytes becoming visible, 

 still translucent, ovaries occupy 

 less than 20°? of body cavity; 



Small opaque oocytes clearly vis- 

 ible, marked increase in ovary 

 size (20% to 100^ of body cav- 

 ity) and change from pink to yel- 

 low-orange color, ovary wall thin 

 and transparent; 



Ovary size as in previous stage, 

 large transparent Ihydrating) 

 oocytes visible among smaller 

 opaque oocytes; 



Ovary size as in previous 

 stage, hydrated oocytes 

 larger, easily expressed from 

 ovaries; 



Ovaries flaccid, occupy about 

 20^ of body cavity, greyish ovary 

 wall thickened and wrinkled, 

 some residual oocytes visible 

 within translucent material; 



Chromatin nucleolar stage: very 

 small oocytes, nucleus sur- 

 rounded by a thin layer of dark- 

 blue-stained cytoplasm; 



Perinucleolar stage: oocyte size 

 increases slightly as dark-blue- 

 stained cytoplasm thickens, 

 nucleoli appear at the periphery 

 of nucleus; 



Cortical alveoli stage: appear- 

 ance of cortical alveoli in pale- 

 blue-stained cytoplasm, pink- 

 stained zona radiata distinguish- 

 able, oil vesicles appearing, 

 lampbrush chromosomes often 

 visible in the nucleus; 



Yolk stage: marked increase in 

 oocyte size, cytoplasm filled with 

 pink-stained yolk granules, cor- 

 tical alveoli and oil vesicles in- 

 crease in size and number; de- 

 generating postovulatory fol- 

 licles visible if spawning has 

 started; 



Nuclear migration stage: migra- 

 tion of nucleus to periphery of 

 oocyte, fusion of yolk granules 

 into yolk plates; fusion of oil 

 vesicles into the oil droplet; de- 

 generating postovulatory fol- 

 licles visible if spawning has 

 started; 



Hydration stage: further in- 

 crease in size of oocytes, all yolk 

 granules fused into a few plates; 



Postovulatory follicles clearly 

 visible, no yolked oocytes left 

 except for a few undergoing atre- 

 sia; structure of ovaries gener- 

 ally loose, hydrated oocytes may 

 be present in lumen; 



Cytoplasm homogeneous, brown- 

 ish and transparent, compara- 

 tively large dark nucleus; 



Oocytes more or less spherical, 

 cytoplasm thickened, darker, 

 granular, but still translucent, 

 nucleus still visible; 



Oocytes dark, completely opaque, 

 size increasing with develop- 

 ment, nucleus occluded; degen- 

 erating postovulatory follicles 

 visible if spawning has started; 



Occurrence of partly translucent 

 oocytes (hydrating), yolk plates 

 visible;degenerating postovu- 

 latory follicles visible if spawn- 

 ing has started; 



Occurrence of very large, almost 

 totally translucent oocytes, oil 

 droplet visible; 



Postovulatory follicles visible, 

 remaining yolked oocytes at 

 early stage of atresia; 



continued 



