a1 Alfred Wegener Institute for Polar and Marine Research, Am Handelshafen 12, 27570 Bremerhaven, Germany
a2 Royal Belgian Institute of Natural Sciences, Rue Vautier 29, B-1000 Brussels, Belgium
a3 Biology Department, Nematology Section, Ghent University, Ledeganckstraat 35, B-9000 Ghent, Belgium
The family Monhysteridae is characterized by 17 valid genera, seven of which are known to be free-living, inhabiting marine sediments. In total, 70 valid marine species are ascribed to these seven genera. Overall, the family is characterized by a confused taxonomic history with a large list of synonyms and species inquirendae. The taxonomic problem is not restricted to the old literature, but inconsistencies also appeared in recent studies. The aim of this study is to show the most important diagnostic characters to identify each genus and provide taxonomic tools for species identification. Dichotomous-keys and illustration-guides are attempted for the marine monhysterid species. For the family and each subfamily, tribe and marine genus a brief historical background, diagnosis and a list of valid species is provided. Hereby, we propose to transfer eight species of the genus Thalassomonhystera to the genus Monhystrella.
(Received November 20 2007)
(Accepted February 12 2008)
(Online publication July 22 2008)