The vertical distribution of free living marine nematodes off the west coast is discussed with focus on the community structure. Three transects were selected and ~erticapl rofiles of the most abundant taxon nematoda, was studied to the lowest taxonomic scale. Both nematodes and total meiofauna were found to decline with increase in sediment depth. The diversity decreased towads the lower sediment layers. Nematodes belonging to 12 families were found to occur in the upper and 11 in lower sediment layers. Certain families (Siphonolaimidae, Eurystominidae, Microlaimidae, and Sphaerolaimidae) were represented only in lower sediment layer. The results showed that salinity, temperature, depth and dissolved oxygen as the most important factors defining the existing nematode abundance in the vertical profile of sediment core.

Nematodes from shelf sediments, community structure, west coast of India