De Lestang et al : Reproductive biology of Portunus pelagicus 



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Table 1 



Morphological characteristics of macroscopic stages in the development of the ovaries of Portunus pelagicus and the types of oocytes 

 found in each of those stages. Mean diameters of oocytes at different stages in development are shown in parentheses. 



Maturity stage 



Macroscopic appearance of ovary 



Types of oocytes 



I Immature Relatively small, flattened and off white to ivory in color 



Anterior region is small, and does not displace the hepa- 

 topancreas. The central "H" shaped region, located in the 

 gastric region, is loosely joined to the dorsal surface of the 

 spermathecae. The posterior section, located in the cardiac and 

 intestinal regions, forms two parallel lobes. 



II Early Conspicuously larger than stage-! ovaries, pale yellow, oval 

 development in cross section and slightly nodulated. The anterior region 



marginally displaces the hepatopancreas and the central 

 region envelops the dorsal surface of the spermathecae, and 

 the two lobes of the posterior region are starting to become 

 convoluted. 



III Late Large, yellow, and nodulated. Anterior region displaces the 

 development hepatopancreas, and the central and posterior regions occupy 



almost all of the space in the gastric, posterior and intestinal 

 cavities. Most of the spermathecae are enveloped by ovarian 

 tissue. 



IV Fully mature Very large, deep yellow to orange, and highly nodulated. 



Hepatopancreas is now completely displaced from its former 

 position by the enlargement of the anterior region of the ovary. 

 The gastric, posterior, and intestinal cavities are completely 

 filled with the enlarged central and posterior sections of the 

 ovary. The spermathecae are totally enveloped by the ovary. 



Loosely packed oocytes, comprising oogo- 

 nia (5 ^m) and, to a lesser extent, chromatin 

 nucleolar oocytes (10 ^m) and perinucleolar 

 oocytes (30 ^m). These three types of oocytes 

 are found in each of the next three ovarian 

 stages. 



Yolk-vesicle oocytes (90 ^m) are present for 

 the first time. 



Early yolk-granule oocytes (130 fjm) sur- 

 round small areas of early stage oocytes, 

 and some late yolk vesicle oocytes are 

 present. 



Advanced oocytes all at the late yolk- 

 granule stage (250 /jm). 



Table 2 



Morphological characteristics of stages in the development of the vas deferens of Portunus pelagicus and the location of spermato- 

 phores in those stages. 



Maturity stage 



External appearance of vas deferentia 



Histological appearance of the vas deferentia 



I Immature I Vas deferentia not detectable macroscopically. 



NA 



II Immature II Anterior vas deferentia (AVD) becoming enlarged, middle Spermatophores present in AVD. MVD and PVD 



and posterior vas deferentia (MVD and PVD, respectively) contain no spermatophores. 

 straight and opaque. 



III Mature I AVD and MVD enlarged and white and PVD enlarged and Spermatophores present in AVD and MVD PVD 



convoluted but still opaque. contains no spermatophores. 



Sound to 87.2 mm in the Leschenault Estuary (Fig. 4B). 

 The CWjq's for each of these bodies of water, which were 

 not significantly different (P>0.05) from each other, were 

 significantly less at P < 0.05 or 0.001 than the 96.0 mm 

 determined for male crabs in Shark Bay. 



The CWjq's for males at gonadal maturity in each water 

 body, derived from the prevalence of males with mature go- 

 nads, i.e. stage III (Fig. 4C), differed by only 0.3 to 2.2 mm 

 from those derived for males in each corresponding water 

 body by using the prevalence of morphometrically mature 



males (Fig. 4B). The CWg^'s derived for male crabs from 

 gonadal data in the four southern bodies of water, which 

 ranged only from 86.5 to 88.4 mm, did not differ signifi- 

 cantly (P>0.05 ). However, on the basis of gonadal data, each 

 of these CWjg's differed significantly at P<0.05, 0.01, or 

 0.001 from the 97.0 mm estimated for male crabs in Shark 

 Bay (Fig. 4C). These trends were parallel to those derived 

 from morphometric data (Fig. 4B). 



The logistic curves derived from gonadal data in each of 

 the four southern bodies of water were significantly differ- 



