Development and allometric growth patterns during early larval stages of the spotted sand bass <i>Paralabrax maculatofasciatus</i> (Percoidei: Serranidae)

Abstract

SUMMARY: We describe the allometric growth patterns of Paralabrax maculatofasciatus larvae raised under culture conditions. From hatching to day 30, ten to fifteen larvae were sampled each day and measured using digital photograph software. Morphometric measurements included total length, head length, body length, tail (post anal) length, head depth, body depth, muscle height, tail depth, mouth length and eye diameter. Allometric growth was modeled by a power function and patterns in allometry were described by the growth coefficient (power function exponent). Based on the changes in the growth coefficients we can infer changes in ontogenetic priorities related to developmental stages of the spotted sand bass. During the yolk sac and preflexion stages (TL interval = 1.57 to 4.38 mm) there is an evident priority to enhancing the feeding and swimming capabilities by promoting accelerated growth in the head and tail length. During the flexion stage (TL interval = 4.89 to 7.54 mm), there is a major decrease in the growth coefficients, indicating a change in growth priorities. At the end of the postflexion stage there is an evident tendency to isometry for all the growth coefficients. The present results support the hypothesis of differential growth patterns for primary functions during early ontogeny.