Gametogenic cycle and size at first maturity of the edible snail Buccinanops cochlidium (Neogastropoda: Nassariidae) from San José gulf in Patagonia, Argentina.

AVERBUJ A.; BIGATTI G.; PENCHASZADEH, P.E

MARINE BIOLOGY

SPRINGER

Año: 2010 vol. 157 p. 2229 - 2240

0025-3162

<!-- /* Font Definitions */ @font-face {font-family:"Angsana New"; panose-1:2 2 6 3 5 4 5 2 3 4; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:16777219 0 0 0 65537 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0pt; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman"; mso-bidi-font-family:"Angsana New"; mso-ansi-language:ES; mso-fareast-language:ES; mso-bidi-language:AR-SA;} @page Section1 {size:612.0pt 792.0pt; margin:72.0pt 90.0pt 72.0pt 90.0pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> Abstract Knowledge of the gametogenic cycle and the size at first maturity is a powerful tool in enabling the sustainable exploitation of marine invertebrate fishery resources This study provides information about the reproductive cycle and size at first maturity of the edible snail Buccinanops cochlidium from San José Gulf, Argentina. Sex identification is possible externally only when females carry egg capsules, or after shell removal by the presence of accessory glands or the colour of the gonad. Both the testis and the ovary were tubular structures. The occurrence of parasperm and eusperm was reported in nassariids for the first time in this study. B. cochlidium testes seemed to develop mature sperm all year round without a resting period, although resorption was registered after periods of high evacuation (June - November). Females showed a clear seasonality without a resting period, and proliferation of oogonia throughout the year. Evacuation of mature oocytes measuring over 220 µm occurred mainly in October. Oocyte evacuation was associated with minimum seawater temperature and increasing daylength. Males developed a penis of functional size and mature gametes in their testes at 37 mm in shell length (SL), but only began to mate at 65 mm in SL. Females matured at 80 mm in SL, considering gonad maturity, mating behavior and oviposition altogether. Female SL at first gonadal maturity is close to the male maximum SL, therefore a minimum landing size greater higher than 80 mm in SL would promote the risk of excluding the males from the catches. The present results presented in this study are useful when planning fishery policies aiming to prevent the overexploitation of the resource, if an extensive fishery targeting on this species is developed.