Temporal variation in egg-capsule deposition by Nassarius vibex (Gastropoda: Nassariidae)

• Published in: Invertebrate reproduction & development 2011-06, Vol.55 (2), p.82-90
• Main Authors: Yokoyama, Leonardo Q., Amaral, Antonia Cecília Z.
• Format: Article
• Language: English
• Subjects: Brazil; egg-capsule deposition; Marine; Nassariidae; Nassarius vibex; reproduction
• ISSN: 0792-4259; 0168-8170; 2157-0272
• DOI: 10.1080/07924259.2010.548647

The morphology and the deposition periods of egg capsules by the bruised nassa Nassarius vibex were investigated on two beaches located on the southeast coast of Brazil. The nassariids were associated with the charru mussel Mytella charruana, which forms beds on soft mud-bottoms. A total of 1558 capsules were collected, only from the fronds of the green alga Ulva lactuca, 859 for Camaroeiro Beach and 699 for Cidade Beach. The mean sizes of the egg capsules and numbers of eggs or larvae per capsule were similar on the two beaches, as were the periods of capsule deposition. At Camaroeiro Beach, capsules first appeared in May 2006, reached a peak in August 2006, and disappeared in December 2006. At Cidade Beach, the first capsules were recorded in July 2006, with a peak in August 2006. A second peak was also observed at this beach between January 2007 and April 2007. The two periods of deposition recorded at the latter beach may indicate two periods of recruitment in the same year for N. vibex. Regarding the influence of intertidal level on capsule deposition, there was a significant difference in the number of capsules between the levels at Camaroeiro Beach (F = 7.445, p