DNA barcoding in marine nematodes: Successes and pitfalls

Abstract

The phylum Nematoda is one of the most diverse and abundant in every ecological niche including terrestrial and aquatic environments. It has been estimated that the abundance of nematodes can reach up to 108individuals per square metre. Like any other environment, sedimentary layer of marine environments are rich in benthic fauna and free-living marine nematodes constitute an important component of benthic domain. These organisms are present in all types of marine habitat including from shallow coastal environment to deep-sea. The structural and functional organization of nematode assemblages can provide precious information on the ‘health’ of ecosystem in which they live, and they are widely recognized as excellent bioindicators of natural and anthropogenic disturbances. The long term success of DNA barcoding as a tool for speeding up identification of marine nematodes during biodiversity and ecosystem monitoring studies will also depend on large scale international efforts such as along the line of Census of Marine Life (CoML) programs. To conclude, morpho-taxonomy coupled with DNA taxonomy using DNA barcoding as a technique could be implemented for undertaking studies on marine nematodes.