Some Aspects of Ionic and Osmotic Regulation in Tisbe [Copepoda, Harpacticoida] in Relation to Polymorphism and Geographical Distribution

• Published in: Journal of the Marine Biological Association of the United Kingdom
• Main Authors: Battaglia, B., Bryan, G. W.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 1964
• Subjects: Aquatic Science; Copepods; Tisbe furcata
• Online Access: http://dx.doi.org/10.1017/s0025315400024632; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0025315400024632

Ability to tolerate low salinities has been compared in homozygous adult females of the trifasciata and violacea forms of the polymorphic copepod Tisbe reticulata from Chioggia (lagoon of Venice). Both forms appear to be equally capable of tolerating sea-water concentrations of between 100 and 33 %. Further comparison with the trifasciata form of T. reticulata from Plymouth and with three different geographical populations of Tisbe furcata has shown that these copepods are rather less tolerant. A study of ionic regulation using the isotopes 22 Na, 42 K and 137 Cs has shown that in diluted sea water T. reticulata does not control the body Na concentration but does control the K concentration. Exchange rates for 42 K and 137 Cs are higher in the violacea than in the trifasciata forms of T. reticulata from Chioggia and the difference may have an adaptive nature although its significance is not clear. With regard to 42 K, the difference between the two polymorphic forms from the same population of T. reticulata is greater than that between the three different geographical populations of T. furcata . This serves to add more emphasis to the fact that colour polymorphism in T. reticulata can be associated with other processes.