SKELETON WEIGHT-FREE OXYGEN-CONSUMPTION RELATED TO ADAPTATIONS TO ENVIRONMENT AND HABITS OF 6 CRUSTACEAN SPECIES

Abstract

1. Oxygen consumption in six crustacean species from the continental shelf of the NW Gulf of Mexico was related to the ash free weight per dry weight (afdw) gram of the tissue excluding the exoskeleton, suggesting a close relationship to their life strategies. 2. Dry weight exoskeleton proportion varied among species, with highest values recorded in callapid brachyuran crab species (46.8-52.5%) against the values recorded in portunid crab (45.8-48%) and the shrimp species (26.7-35.7%). 3. Oxygen consumption was related to afdw in each species according to the expression y = ax(b), with b values ranging from 0.68 to 2.92. 4. Rates of oxygen consumption per afdw/dw were larger in shrimps than in portunids and callapids, and was related to the morphophysiology and lifestyle of six species described

the former as the morphological design of the exoskeleton versus the muscle content in the species and the latter as the activity rate in the environment. 5. The oxygen extraction efficiency, calculated from oxygen consumption, was higher in the eurytopic species Penaeus aztecus and Callinectes similis than in species restricted to the marine environment, hence considered as a response to environmental fluctuations.