A list of the genera of living organisms known or believed to contain luminous species is provided in the Appendix, in a systematic context. The constraints on the accuracy of such a list and some aspects of the apparent distribution of bioluminescence are discussed.

No abstract

This study evaluates the role of protozoa in larval fish feeding by describing protozoa in larval fish diets and testing the hypothesis that, in the Irish Sea, larval fish feed on protozoan prey at rates that potentially sustain their food requirements. Gut contents of 11 taxonomic groups of larval fish were examined, and protist prey occurred in the diet of all of them. Protozoan prey were identified, which provided an insight into their trophic role. Most of the protozoan prey were autotrophic or mixotrophic. In general, larval fish diets were constant over the spring/summer period, regardless of prey availability in the field and the composition of larval fish assemblage (taxonomy and size). A laboratory experiment on ingestion rates of flounder larvae as a function of ciliates concentration was conducted. Combined laboratory and field data showed that, in the Irish Sea, it is unlikely that ciliates are often the primary food source of flounder larvae, and, by implication, other larval fish as well. However, ciliates and other protozoa could be a substantial component of the larval fish diet, and they may potentially prevent food limitation.

The aim of this work was to establish the role of imidazolopyrazines in the bioluminescence of copepods and other marine organisms. A highly sensitive assay (down to 10-17 mol) for coelenterazine was established using reactivation of the CaZ+-activated photoprotein obelin, and for vargulin using Vargula hilgendorfi luciferase. Coelenterazine and its luciferase was found in all (8 species) the luminous copepods examined. In Euaugaptilus species more than 90% of the luciferase was found in the legs, with the luminous cells, but over 40% of the coelenterazine was found in the bodies. Coelenterazine was found in luminous organisms from six phyla: Sarcomastigophora (Radiolaria), Cnidaria, Ctenophora, Arthropoda, Mollusca. Chordata (Pisces). Only in the first three of these were Ca 2 +-activated photoproteins present.