Short Communications Pakistan J. Zool., vol. 40(3), pp. 217-221, 2008. 0030-9923/2008/0003-0217 $ 8.00/0 Copyright 2008 Zoological Society of Pakistan. is known about their reproduction, more so about SEASONAL VARIATIONS IN THE the reproduction of E. verrucosa. The aim of present OVARY AND TESTIS OF ERIPHIA study is to determine seasonal variation of gonads in VERRUCOSA (FORSKÅL, 1775) E. verrucosa in its natural environment and to (CRUSTACEA: DECAPODA) FROM correlate this development with temperature, salinity and dissolved oxygen. This could provide useful KARABURUN, SW BLACK SEA information for management of this commercially important species in the protection areas (Kennely Abstract.- The present study describes the gametogenic cycle in an economically and Watkins, J. Crust. Biol., Lawrence, 14: 146- important and endangered crab species Eriphia 150, 1994). verrucosa (Forskål, 1775) in Black Sea. The ovary and testis developed throughout the year and spawning occurred from late July to the end of August. The change in water temperature correlated with the reproductive cycle of E. verrucosa, whereas the salinity and dissolved oxygen did not show any correlation. Key words: Reproductive cycle, seasonal variation in gonad. Crabs are considered healthy food for their high quality protein and small amount of fat and carbohydrates (Skonberg and Perkins, Fd. Chem., Fig. 1. Map of the investigated area. 77: 401-404, 2002; Musaiger and Al-Rumaidh, Int. J. Fd. Sci. Nutr., 56: 231-235, 2005; Küçükgülmez Materials and methods et al., Int. J. Fd. Sci. Technol., 41: 1023-1026, The crab samples were collected by using 2006). Eriphia verrucosa is a commercial crab trammel net at the depth of 1 to 5 m in Karaburun species in Black Sea in Turkey (Holthuis, Vrais located in the coast of the Western Black Sea every crabes. Fiches FAO d'identification des espéces month during September 2004 and August 2005 pour les besoins de la peche. Mediterranée et Mer (Fig. 1). The species was identified using a range of Noire. Zone de péche 37, 1, Végetaux et invertébres references (Bouvier, Décapodes Marcheurs. Faune FAO, Rome, pp. 321-367, 1987; Altinelataman and de France (ed. P. Lechevalier et Fils), pp. 404, Dincer, Lebensmittelhyg., 58: 132-135, 2007), Paris, 1940; Zariquiey-Alvarez, Crustáceos which has been fished out in such a large amount Decápodos Mediterréneos. Instituto Español de during the past years that it has now reached the Estudios Mediterráneos, pp. 181, Barcelona, 1946, level of endangered species in the Black Sea (EFT, Crustáceos Decápodos Ibéricos. Investigación http://www.cevre.org.tr/Karadeniz 2004). Pesquera, 32: pp. 1-510, Barcelona, 1968; Demir, Most of the studies on the Black Sea crabs are 1952; Holthuis, Vrais Crabes. Fiches FAO on systematics of crabs (Holthuis, Zool. Verh., 47: d'identification des espéces pour les besoins de la 1-67, 1961; Caspers, Rapp. Comm. Int. Mer. Médit., peche. Mediterranée et Mer Noire. Zone de péche 19: 107-115, 1968; Ates, Turkish. J. Zool., 23: 115- 37, 1, Végetaux et invertébres. FAO, Rome, pp. 118, 1999; Bilgin and Celik, Fırat Üniv. Fen ve 321-367, 1987). The crabs transferred to laboratory Müh. Bil. Dergisi, 16: 337-345, 2004), whereas little alive in sea water were killed by exposing them to a temperature of –20ºC for 15-20 minutes. The 218 SHORT COMMUNICATIONS carapace width (CW) and length (CL) of all crabs February and the highest temperature (25.6°C) in were measured with a vernier caliper at the nearest August. During this study, the salinity ranged 0,01 mm. The female and the male gonads were between 16.6 %о and 17.9 %о, the lowest was in taken out and quickly fixed in Bouin’s solution for February and May and the highest in August. The 12 hours at 20ºC. The 5-6 µm thick histological oxygen content of sea water in sampling stations sections were cut and stained with haematoxylin and ranged between 6.8 and 19.5 mg l-1. The lowest eosin (H&E) (Humason, Animal tissue techniques. oxygen content was measured in May and the H.W. Freeman and Company, San Francisco, 1972). highest in June. The monthly average values of The histological sections were studied under water temperature (ºC), salinity (‰), and dissolved light microscope for determining different stages of oxygen (mg l-1) are shown and the correlation reproductive cycle. Following parameters were used between these values is given in Figure 2. for characterizing different reproductive stages. The stage 1 was designated as slightly developed stage Temperature Salinity Dissolved Oxygen characterized by thin, brown red ovary in colour; 30 stage 2 designated as moderately developed stage 25 characterized by lobed brown red ovary; stage 3 20 designated as developed stage is characterized by 15 oxygen 10 ovary with well-developed lobes brown red in 5 Temparature, 0 colour; stage 4 designated as well developed stage Salinity,Dissolved by ovary with well-developed lobes and fill the May July March anterior portion of carapace; and stage 5 designated January SeptemberNovember Months as mature stage is characterized by ovary with well- developed lobes and fully matured eggs which fill the anterior portion of carapace. In males, maturity is established by the presence of spermatophores in the vas deferens. Similar criteria were used by Kwei (Zool. J. Linnean Soc., 64: 151-175, 1978) and Armstrong (N. Z. J. Mar. Freshw. Res., 22: 529-536, 1988) for the male Callinectes latimanus and by Watson (J. Fish. Res. Bd. Canada, 27: 1607-1616, 1970) for the male spider crab, Chionoecetes bairdi. Some ecological parameters such as salinity (‰), temperature (ºC) and dissolved oxygen (mg l-1) were measured at the sampling site. The Mohr- Fig. 2. The correlation between Knudsen method (Ivanoff, Introduction temperature (ºC), salinity (‰), and dissolved oxygen (mg l-1) values with the diameter of al'océanographie. Tome I. librairie Vuibert, pp. eggs of Eriphia verrucosa. 642, Paris, 1972) was used to measure salinity and the Winkler’s method (Winkler, Berlin Deuth. Females Chem. Ges., 21: 2843-2855, 1888) to measure Stages of development of ovaries and dissolved oxygen (DO). histological structures are shown in Figure 3. As oogenesis begins, oogonia (57 µm in diameter) in Results the germinative zones of the ovary begin to produce In the present study, 142 males and 61 previtellogenic oocytes (143 µm in diameter) in females were studied with CL 53-73 mm and CW September and October (Stage 1, Fig. 3 A, B). As 71-93 mm for males, and with CL 42-57 mm and development continues the ovary increases in width with CW 58-80 mm for females. In sample stations, and the oocytes increase in size (231-364 µm) with the temperature ranged between 5.5 and 25.6°C. large nuclei and visible nucleoli, during November The lowest temperature (5.5°C) was measured in and February (Stage 2, Fig. 3 C-F). At this stage, SHORT COMMUNICATIONS 219 some oocytes undergo early vitellogenesis and then increase in ovary volume and the oocyte is 406-457 all oocytes pass into vitellogenic stage. There is an Fig. 3. Histology of ovarian (A-L) and testis (M-O) development of Eriphia verrucosa. A-B, Stage 1; C-F, Stage 2; G-J, Stage 3-4; K, Stage 5; L, Egg carried on the pleopods, M, Transverse section of testis; N, Transverse section of 220 SHORT COMMUNICATIONS vas deferens; O, Spermatophore has been found in the reproductive system of male E. verrucosa. Staining: haematoxylin and eosin; Magnification A-L, N, x360; M, x3600; O, X1040. µm in diameter between March and June (Stages 3- Botucatu, São Paulo, 158p, 1994), Callinectes 4, Fig. 3G-J). Most of the oocyte growth occurs danae (Costa and Negreiros-Fransozo, Crustaceana, between stages 3-5 content increase. Yolk content 71: 615-627, 1998), and Hepatus pudibundus increased in the oocytes as development continues, (Reigada and Negreiros-Fransozo, 2000) showed a and in histological preparations the nuclei become continuous reproductive pattern. In the males, the more obscured by yolk granules in July (Stage 5, spermatocytes continued to develop throughout the Fig. 3K). Oocyte size reaches about 481 µm at this year and spermatophores begin to mature mostly in stage. Eggs carried on the pleopods of the female early July. In tropical waters, however, berried are 601 µm in diameter in August (Fig 3L). females often occur throughout the year and spawning is often continual (Shields and Wood, Males Mar. Ecol. Prog. Ser., 92: 159-170, 1993). Thus, the The vas deferens of mature males is always reproductive biology of E. verrucosa in Karaburun full of seminal fluid containing many spherical, (SW Black Sea) differs from that in the tropics or fully developed spermatophores. All spermatogonial subtropics, with spawning only occurring at certain in a particular lobe of the testis are at the same stage times of the year. Such a strong seasonal pattern of of development. Monthly histological examination spawning is closely correlated with seasonal of testis of mature males showed that mature and changes in sea temperature and implies strong immature spermatocytes are always present seasonal growth (Xiao, Canadian J. Fish. aquat. throughout 12 months. No relative increase in the Sci., 53: 1675-1682, 1996; Xiao, Fish. Bull., 97: size of the testis was observed at any time of the 690-701, 1999; Xiao and McShane, Fish. Res., 37: year. Figure 3M shows a typical section of testis, 66-77, 2000; Kumar et al., J. Mar. biol. Assoc. U.K., Figure 3N shows vas deferens, and Figure 3O shows 83: 983-994, 2003). spermatophores found in the experiments carried out At sampling stations, the highest dissolved in July. oxygen concentration observed in June, when the sea temperature was 22°C.