Spawning and intra-capsular development of Neritina zebra (Bruguiere, 1792) (Mollusca: Gastropoda: Neritidae) under laboratory conditions

The gastropod Neritina zebra is distributed in Suriname and along the coast of Brazil, where it lives Oil Muddy bottoms of brackish water environments. The objectives Of this Study were to describe the spawning off. zebra and to investigate its embryonic and larval development under laboratory conditions. The egg capsules are oval. The surface of the capsule in contact with the substratum is flat, while the opposite surface is convex and covered by sand grains. One end has a small suture. A thin membrane Surrounds the eggs. Inside the capsules, the developing embryos and larvae are Surrounded by fluid (albuminous liquid). N. zebra has mixed development. It was not possible to observe settlement and metamorphosis of veligers in the laboratory due to their death a few days after hatching. In the 2007 experiment, the capsules opened, releasing veligers, after 21 days. In 2008, the capsules opened after 26 or 27 days after the salinity was reduced from 15 to 10 ppt. N. zebra may be amphidromous, as are others of the same genus which inhabit environments with a strong freshwater influence and have planktotrophic larvae.