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Email the author (Login required) Embryonic and early larval development of Gari solida (Gray, 1828) (Bivalvia: Psammobiidae)
DOI: https://doi.org/10.3856/vol42-issue1-fulltext-25
Abstract
Early development of the culengue (Gari solida) (Gray, 1828) to the initial stage of veliger larva from two spawning carried out in the summer of 2009. Spawning was induced in 80 mature specimens, between 50-60 mm of valve shell length, by drying at room temperature for about 30 min, followed by a thermal shock treatment (12-14° C and 23-25° C). These breeders were preconditioned for 90 days at 14° C on the average, and fed with Isochrysis aff galbana (T-Iso), Chaetoceros calicitrans and Tetraselmis suecica, in 1:1:1 ratio, at a concentration of 300.000 cell mL-1. The oocytes were fertilized at a proportion of 10:1 sperm/oocyte, and incubated in 50 L-tanks at 15 ± 0.8°C, without aeration, containing 1µm-filtered and UVirradiated seawater. Observations and measurements from embryogenesis to D-shaped veliger larva were made; the duration of each developmental stage was recorded. Embryogenesis was completed between 23 to 24 h post- fertilization (pf) and the D-shaped larval stage was achieved within 36-37 h pf, measuring 78 ± 4 µm in length. A gelatinous covering or jelly coat surrounds the oocyte and remains until fully developed freeswimming D-shaped larva, between 50-52 h pf. This work constitutes a first report on the early development of G. solida. To deepen this knowledge it would be desirable to include electron microscopy techniques in future studies.
