Level, content, and caloric equivalents of the lipid, carbohydrate, and protein in the body components of Luidia clathrata (echinodermata: asteroidea: platyasterida) in Tampa bay

Abstract

The body components of the primitive platyasterid starfish, Luidia clathrata (Say) have been characterized according to season, reproductive, and nutritional condition. The animal has been ‘reconstructed’ in terms of the wet and dry weights, the weight of organic matter, and the caloric equivalents of the body components in early summer (when there are no gonads and the pyloric caeca are small), in autumn (just prior to initiation of gonadal development and at maximal caeca size), and in early spring (at maximal gonad size). The body wall is always the most significant component in terms of wet and dry weights. In terms of organic matter and calories, the pyloric caeca are the most significant compartment in the fall and, together with the gonads, in the spring. On starvation for one month, the decrease in the size of the pyloric caeca is calculated to have produced 2.048 kcal. The energy requirement over the period, calculated from Q o 2 values, is 2.112 kcal. There was no change in biochemical composition of the pyloric caeca with starvation, suggesting that energy production came about through cell destruction rather than preferential utilization of cellular nutrient stores. Lack of extreme change in the composition of the pyloric caeca with size through the year also suggests that energy deposition in the organ is primarily by change in cell number and not by cell size.