Reproduction and imposex in the edible snail Adelomelon ancilla from northern Patagonia, Argentina

Abstract

The edible volutid snail Adelomelon ancilla occurs on the Argentine coast and may have the capacity to serve as source of support for local Wsheries. However, knowledge of its reproduction is lacking. Over 3 years (from September 2000 to July 2004) we studied the oviposition at Golfo Nuevo, Patagonia by diving. Monthly collections were performed to examine gonadal stages histologically during 2002-2003. Gamete development stages corresponded with the expected period for oviposition occurring from July to November, a time of increasing day length. Oviposition also took place in March when water temperature attained a maximum of 18°C. Following the spawning period, remaining gametes were resorpted in both sexes. Males contained sperm throughout the year, parasperm and eusperm forms were found within the same acinus. Oogonia/oocytes ranged from 20 to 240 m in diameter during oogenesis. Females commenced laying egg capsules from a shell length of 114 mm. Reproduction is compared with other Wshable volutid snails from the Argentine shelf, and suggests the need to apply certain Wshing restrictions if the resource begins to be utilized commercially. The imposex condition was found in snails from some shipping areas. The frequency of this condition declined with distance from the port.Communicated by M. Byrne.

Reproductive cycle and oviposition inZidona dufresnei(Caenogastropoda: Volutidae) from northern Patagonia, Argentina

“…In males, the observation of different gametogenic stages in the same individual is consistent with the observations made by Giménez & Penchaszadeh (2002) in the same species and by Cledón et al (2005) in A. brasiliana, in O. magellanica and Penchaszadeh et al (2009) in A. ancilla.…”

“…The mean oocyte size of mature oocytes (about 170 µm) was consistent with that seen by Giménez & Penchaszadeh (2002) for the same species and was within the range of other volutids in the Argentine Sea (Cledón et al 2005;Penchaszadeh et al 2009). The low number of mature oocytes ready to be evacuated, and the cell diversity observed throughout the year (i.e.…”

“…As a consequence, the process of phagocytosis of the remaining oocytes seems crucial to reuse the energy in the same reproductive period. In other volutids such as V. musica and Adelomelon ancilla (Penchaszadeh et al 2009;Peralta 2012), this phenomenon was also observed throughout the year.…”

“…For instance, there is extensive information on reproductive aspects and gonadal cycles of the volutids Zidona dufresnei (Donovan, 1823) (Giménez & Penchaszadeh 2002;Giménez et al 2008), Adelomelon brasiliana (Lamarck, 1811) (Cledón et al 2005), Odontocymbiola magellanica (Gmelin, 1791) , Adelomelon ancilla (Lightfoot, 1786) (Penchaszadeh et al 2009) and Voluta musica Linnaeus, 1758 (Rangel et al 2011;Peralta 2012).…”

Evaluation of the use of Olivella minuta (Gastropoda, Olividae) and Hastula cinerea (Gastropoda, Terebridae) as TBT sentinels for sandy coastal habitats

“…In South America, imposex and TBT environmental levels (surface sediments and biota samples) have been detected in Argentina (Penchaszadeh et al 2001;Bigatti et al 2009;Penchaszadeh et al 2009;Arrighetti and Penchaszadeh 2010), Venezuela (Paz-Villarraga et al 2015), Ecuador (Castro et al 2012b), and Peru (Castro and Fillmann 2012). On the Brazilian coast, particularly in recent years, imposex associated to TBT has been reported in the southern (Castro et al 2012a), southeastern (Fernandez et al 2005;Quadros et al 2009;Costa et al 2009;Cardoso et al 2009;Borges et al 2013), and northeastern regions (Camillo et al 2004;Castro et al 2004;Castro et al 2007a, b;Fernandez et al 2007;Castro et al 2008;Lima-Verde et al 2010;Azevedo et al 2012).…”