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Sağlam, H., Düzgüneş, E., and Öğüt, H. 2009. Reproductive ecology of the invasive whelk Rapana venosa Valenciennes, 1846, in the southeastern Black Sea (Gastropoda: Muricidae). – ICES Journal of Marine Science, 66: 1865–1867. The reproductive ecology of the invasive whelk Rapana venosa Valenciennes, 1846 (Gastropoda: Muricidae) was examined in Surmene, southeastern Black Sea, Turkey, using monthly samples of individuals collected by dredging from November 1999 to October 2000. The observed sex ratio (F:M) was 1:1.6; mean shell length at sexual maturity was 40 mm. Changes in the ovary and testis indices indicated that spawning mainly occurred between June and early August in the southeastern Black Sea.
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Sağlam et al. (2009) studied this question.
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