Importance of light and larval morphology in starvation resistance and feeding ability of newly hatched marine ornamental shrimps Lysmata spp. (Decapoda: Hippolytidae)

The present work evaluates the resistance of newly hatched Lysmata amboinensis, Lysmata ankeri, L. debelius and Lysmata seticaudata larvae to 24, 48, 72, 96 and 120 h of starvation after hatching, as well as their ability to capture newly hatched Artemia nauplii and enriched metanauplii, under different light regimes (24, 12 and 0 h of light). Additionally, it analyses the feeding and swimming behavior of newly hatched larvae and compares their morphological and biometrical features. L. ankeri and L. seticaudata displayed higher resistance to starvation than L. amboinensis and L. debelius, molting to zoea II in the absence of food. Larvae starved for longer periods and kept in darkness displayed higher survival rates, probably due to a lower energy consumption induced by reduced swimming activity. Light regimes did not influence Lysmata ability to capture larval preys, reinforcing the idea that these larvae do not display true hunting behaviors, rather relying on chance encounters with dietary preys. All Lysmata larvae consumed similar levels of Artemia nauplii, while L. ankeri and L. seticaudata were able to consume a significantly higher amount of enriched metanauplii than L. amboinensis and L. debelius. Interspecific larval size variability, similar swimming ability and the inexistence of morphological features more specialized for prey capture in L. ankeri or L. seticaudata larvae exclude larval morphology and biometry as explanations for the different consumption rates recorded. The ability of Lysmata larvae to capture large dietary preys opens good perspectives for the use of inert diets at an early stage.