Haemolymph acid‐base status of the stalked barnacle Calantica spinosa

Abstract

Haemolymph pH and P_co2 were determined for the pedunculate intertidal barnacle Calantica spinosa (Quoy & Gaimard) during submersion and aerial exposure at 15°C. The increase in haemolymph P_co2 (4.1 to 7.1 mm Hg) and concomitant decrease in haemolymph pH (7.36 to 7.22) described for C. spinosa during exposure in air are characteristic for aquatic invertebrates during short‐term emersion. In vivo haemolymph pH during submergence was determined for barnacles acclimated to a range of temperatures between 5 and 25°C. The pH of Calantica haemolymph is maintained at a constant relative alkalinity of ∼0.2 pH units. In vivo haemolymph pH varies with temperature (T, °C) according to the relationship ?pH/?T = ‐0.0192 pH units °C^‐1.

Keywords:

• Calantica spinosa
• barnacle
• intertidal
• acid‐base status
• haemolymph

Notes

Present address: c/‐ Dr E. W. Taylor, Department of Zoology and Comparative Physiology, University of Birmingham, P. O. Box 363, Birmingham B15 2TT, United Kingdom