Marine nematodes play an important role in many ecosystems. Their roles in bioturbation, nutrient decomposition and nutrient mineralization as well as in food web interactions have been well reported. In addition, their sensitivity to changes in the environment caused by pollution has been exploited in their usage as bio-indicators in the environment. Despite their important roles, discriminating species within taxa groups remains a difficult task that requires great taxonomic expertise, leaving a greater part of the knowledge on nematode species diversity in a state of enigma. This book...