The marine gastropod Linatella caudata (Gmelin, 1791) represents a serious threat to bivalve aquaculture facilities as a consequence of its intensive predatory behaviour on these mollusks of commercial interest. We study the fecundity and embryonary development of this snail species. The developmental sequences of the ovigerous capsule including the “immature”, early mature and advanced mature or final stages. Regarding fecundity, six ovigerous capsules masses (eggs mass) were studied and showed a variable number of ovigerous capsules (101-203) and eggs per capsule (83-198). This may correspond to a different total number of eggs in each ovigerous capsule mass, within the range of ca. 8 400 to 40 200 eggs. In the embriogenesis, the blastula, gastrula, trochophore and veliger stages occurred on days 2, 4, 6 and 18 of their embryonic development, respectively, whereas larval hatching was observed at day 26. Linatella caudata hatches from the ovigerous capsule as apelagic larvae (being a planktotrophic larvae).