The diversity and abundance of seagrass dwelling harpacticoid copepods are determined. The use of harpacticoids as a sensitive tool in pollution monitoring is evaluated by means of difference in diversity between the Gazi Bay and English point harpacticoid assemblages and the use of TWINSPAN analysis. This is completed by a brief discussion of the usefulness of the different diversity indices. A second part comprises (re) descriptions of some species together with some remarks on interesting features of other species and an updating of geographical distribution.