Coelenterazine-dependent Bioluminescence in the Cyclopoid Copepod, Triconia conifera.

Species in the cyclopoid copepod Triconia are known to be bioluminescent, emitting blue light by mechanical stimulus. In this study in Triconica conifera, we identified the presence of luciferase activity to coelenterazine, a substrate for the bioluminescence in various marine taxa such as luminous cnidarians, fishes, and crustaceans including calanoid copepods. The molecular size estimated by gel-filtration chromatography and pH dependency of the luciferase activity were similar to those in calanoid copepods.

Lack of congruence in species diversity indices and community structures of planktonic groups based on local environmental factors.

The importance of analyzing the determinants of biodiversity and community composition by using multiple trophic levels is well recognized; however, relevant data are lacking. In the present study, we investigated variations in species diversity indices and community structures of the plankton taxonomic groups-zooplankton, rotifers, ciliates, and phytoplankton-under a range of local environmental factors in pond ecosystems. For each planktonic group, we estimated the species diversity index by using linear models and analyzed the community structure by using canonical correspondence analysis.