We are grateful to Dr. F. Riemann for stimulating discussions and his kind help with literature and nematode identifications. We are sincerely thankful to Dr. P. Martínez for interesting discussions and technical „tips“ in the laboratory. We wish to thank Drs L. Levin and V. Gallardo for inviting one of us (CN) to participate in the cruise Panorama Leg 3a aboard the R/V Melville. Special thanks to J. Sellanes for valuable assistance on board and in the lab. We would like to thank Dr. T. Glatzel for kind help throughout SEM-microscopy process, and Drs. T. Höpner and K.-H. Schminke for laboratory facilities. Ship time was supported by the University of California. C. Neira was supported by the ICBM and the FONDAP-Humboldt Program.