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Email the author (Login required) Effect of temperature and photoperiod on the early development of nudibranch Diaulula punctuolata (d’Orbigny, 1837) under laboratory conditions
DOI: https://doi.org/10.3856/vol44-issue3-fulltext-9
Abstract
Temperature plays an important role in both the development and growth of marine invertebrates; furthermore, it has been observed that photoperiod significantly affects feeding, growth and larval survival. In this study we evaluated the effect of temperatures of 10° and 16°C and photoperiods of 8:16 and 16:8 on early development, hatching and larval survival in the nudibranch Diaulula punctuolata, under laboratory conditions. At 16oC/8:16, hatching occurred between 10 and 11 days post-spawning (dps), with a physiological time of 162.3 ± 10.1 degree day (d°C); while at 10°C/8:16, hatching took place between 17 and 20 dps; 200.5 ± 27.4 d°C (F = 366.6; P ˂ 0.05). The highest hatching percentage, 82.9%, was obtained at 10°C (F = 16.63; P ˂ 0.05) coinciding with environmental conditions present during the adult collection season. Larvae obtained at 16°C were larger (146.3 ± 0.8 µm) than those at 10°C (140.4 ± 0.5 µm) (F = 212; P ˂ 0.05). Nevertheless, survival time was greater at 10°C/8:16 (21 dps), which could be associated with greater nutrient accumulation during embryonic development. Both embryonic and larval development are dependents on temperature, but not on photoperiod; an increase in temperature from 10º to 16°C, reduced the chronological time required up to hatching by 45.6 ± 3.4%. Photoperiod only affected larval survival at 10°C.
