ISSN:
1365-2109
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
This work describes for the first time the embryonic development of the tropical scallop Nodipecten nodosus. Larval and post-larval growth parameters and some characteristics of larvae shell morphology were also ascertained. The larvae were obtained from the induced spawning of a group of broodstocks under controlled laboratory conditions. After fertilization, larval cultivation was carried out in conical tanks at a temperature of 26–27 °C. Larval density was controlled as a function of larval growth to give 10, 5 and 3 larvae mL−1 from days 1, 3 and 8 respectively. The larvae were nourished with a 1:1 mix of Isochrysis galbana (clone T-ISO) and Chaetoceros gracilis in portions varying between 30 000 and 70 000 cells mL−1. Expulsion of polar groups was observed 5 and 15 min after fertilization, whereas the first cellular division occurred after 30 min. The first gastrule ciliates and trocophore larvae were noted after 8 and 18 h had elapsed, respectively, whereas prodissoconch I, or D-larvae, were discerned after 26 h. Subsequently, larvae with prodissoconch II or veliger-conch appeared at 30 h. Larval development continued for 10–12 days, followed by metamorphosis, at an approximate length of 208–230 µm. The growth of the post-larvae was evaluated for 9 days. Larval and post-larval growth corresponded to the linear equations L = 71.85 + 10.85t, r2 = 0.99, and L = 44.09 + 17.81t, r2 = 0.94 respectively. Accordingly, larval morphology and size disparities are discussed with respect to other tropical pectinids.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1046/j.1365-2109.2002.00692.x
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